Questioning the "science" behind FW planted tanks

[Anonymous]

I've recently gotten interested in freshwater planted tanks, an aspect of the hobby that didn't really exist when I last kept freshwater tanks in the early 80s. I've been doing some research, lots of reading up and asking questions... and the more I discover, the more convinced I am that a lot of the freshwater planted methodologies are, well, insane.

There are two main methodologies, it seems. The first is followed by comparatively few, and largely dismissed by most. Referred to as the Walstad method (named after the author who promulgates it, Diane Walstad) it's a semi-natural approach focusing on the use of sunlight, potting soil as a substrate and generally a rather "wild" look. It is reminiscent of some things discussed by Adey in "Dynamic Aquaria", but seems a lot less polished.

The second method is practiced by the majority of planted tank keepers. It revolves around:
- 2-4w per gallon of light, with anything over 2wpg not recommended unless one plans to use pressurized Co2 and dose fertilizers extensively (see below)
- a deep substrate, usually composed of special commercially available products that are extremely high in fertilizer content
- a steady supply of injected Co2 ("natural" levels of CO2 in freshwater are about 3ppm, recommended levels in a planted tank are as high as 30ppm)
- HEAVY planting with a large amount of plant bio-mass right from day one
- heavy dosing of liquid fertilizers, such as nitrate, phosphate, iron, etc
- regular huge water changes, as much as 50% as often as weekly

It's that last that really stuck out for me. Try as I might, I can't come up with a reason that makes sense for why this should be neccessary. Or rather, I can come up with one, but that one sort of invalidates a great deal of the methodology.

Now, I freely admit, water changes are a lot less hassle on a freshwater tank than on a saltwater one, and they are always beneficial. Still, the amounts and frequencies being suggested seem…. Excessive. Needlessly so.

What is it that these water changes are supposed to be removing? Fish waste seems like the first obvious answer, but in truth this shouldn’t matter. Both liquid and solid waste from the fish will be metabolized by the plants, and are essentially composed of exactly the fertilizers it’s suggested be dosed by the aquarist. Likewise uneaten fish food, which tends to be the major introducer of phosphate in reef tanks. The standard ammonia-> nitrite-> nitrate cycle is handled by the plants at every step of the way, and by the tank’s biological filtration media (if any is present). But even then it’s handled a step further; anaerobic bacteria should be present in the depths of the substrate, not to mention within the hardscape elements (rocks, driftwood) themselves. I don’t expect the hardscape elements to function equivalent to the same weight of live rock, but over time they and the deep substrate bed should develop into fairly functional nitrate reducers. But even if they don’t end up contributing much – and I suspect they will, as a 3” deep sand bed in a reef tank harbors enough anaerobic bacteria to handle an entire tank on it’s own – the plants themselves will gladly use nitrate as a nutrient. So fish waste shouldn’t be the reason why these water changes are needed.

I’ve seen a post by a well-respected guru on planted tanks suggest the reason is DOCs, Dissolved Organic Compounds. I’m quite familiar with the concept of DOCs, as anyone who has ever spent several hundred dollars on a protein skimmer should be. But this is freshwater, not a reef… most of the DOC issues that one gets when growing corals simply don’t exist in a freshwater tank. No chemical warfare with anti-growth hormones, terpenoids and outright poisons is occurring. Spent nematocysts and their complex proteins are not breaking down, nor are any of the tank’s inhabitants regularly discarding slimy, mucousy or waxy layers and membranes. Near as I can see, the main DOC issues in a freshwater planted tank might be fish hormones, tannins and the like. None of which should need water changes to be dealt with. Activated carbon and the simple biological process of the compounds breaking down over time should be more than capable of handling DOCs in a freshwater planted tank.

So if it’s not fish waste or DOCs, what is it the water changes are supposed to be removing? Forgive me if I’m being obtuse, but the only other thing I can think of is the substances being deliberately added as fertilizers.

Even if it's not because of the fertilizers, the logic used to justify their use doesn't make a huge amount of sense to me, either. The argument is this:
1. Excessive nutrients in the form of fertilizers (nitrates, phosphates, etc) don't cause algae, excessive lighting and/or ammonia does. (source: Tom Barr)
2. In a tank with good CO2 injection and high lighting, in the absence of high levels of nitrate, phosphate, iron, etc algae will grow, not plants. If high levels of nitrate, phosphate, iron, etc are added to a tank with good CO2 and lighting, plants will grow, not algae.

That doesn't make sense to me. Especially if there is (as recommended) a high bio load of plants in the tank, shouldn't they out compete the algae for a limited supply of nutrients? Especially when they have roots buried in fertilizer rich substrate, and the algae doesn't? Why would providing high levels of nutrients in the water column, and thus accessible to the algae (unlike the nutrients in the soil) prevent algae growth and encourage only plant growth?

Does this make sense to anyone? Is there something I'm missing, or is this whole methodology entirely too reminiscent of the "add a billion additives" phase of the reefkeeping hobby of the early 90s?

 

[Anonymous]

I have maintained both FW planted and salt tanks for up to 6 years continuous with very heavy bioloads and no water changes. In fw with no mechanical filters no circulation not even an air stone.

There is nothing new about this method. I started it based upon Freshwater and marine Aqauriums article feb 1979 by Robert Gaser titled "some old (or are the new?) ideas on aquarium keeping. With two followups in sept/oct that year titled something like leiden aquariums part 2 and 3.

You just start the tanks with tons and tons of plants (marine macro algaes) and let the plants filter and establish the environment. Then add the bioload slowly. With livebearers like platys you wind up with 15-30 fish in a 10g tank in about 6 months. And the population is stable for years and years.

 

[Anonymous]

Bob, I'm not really disagreeing with you (the type of tank you describe does work), but it's kind of entirely aside from what I'm talking about here.

I'm looking for answers for why a particular (and popular, widespread) methodology promotes certain concepts which don't make a lot of sense to me. It may be that I'm completely missing something fundamental, I frankly don't know. But observing the various internet planted tank forums, it seems others who've raised similar points in the past have received a reception akin to posting "sandbeds suck, bare bottom all the way!" in a forum run by Ron Shimek. But I know there are reefers here at reefs.org who enjoy planted tanks, and I'm hoping that someone who has run tanks with this methodology can shed some light on things.

 

[Anonymous]

I understand.

I have seen various methods come in vogue then fall out of fashion. Just like that title of the 79 article.

In the last 4 years or so DSB vrs refugiums with macros (algae turf scrubbers) for instance. And your example of the additives from many years ago.

Truth is all the various methods work and have strengths and weaknesses.

So most just advise whatever works for them.

Plus the industry has the additional consideration of what increases profits.

Plus most people feel they have to be doing something. Even when doing nothing may be the best thing.

Just the way the hobby is. And has been from many years.

 

[Anonymous]

Bob, I'm not really disagreeing with you (the type of tank you describe does work), but it's kind of entirely aside from what I'm talking about here.

I'm looking for answers for why a particular (and popular, widespread) methodology promotes certain concepts which don't make a lot of sense to me. It may be that I'm completely missing something fundamental, I frankly don't know. But observing the various internet planted tank forums, it seems others who've raised similar points in the past have received a reception akin to posting "sandbeds suck, bare bottom all the way!" in a forum run by Ron Shimek. But I know there are reefers here at reefs.org who enjoy planted tanks, and I'm hoping that someone who has run tanks with this methodology can shed some light on things.

i'd be doubtful and suspicious of anything written/said by barr- i think he's waaay out in left field on so many levels it's actually amusing

i stumbled upon his site once and laffed my head off at some of the stuff he was saying, heh

i've always liked large (20-25%) water changes for 'just the breath of fresh air' if nothing else, and because i assume that there are unknowns that buildup in a system

most of the planted tanks i've done have been fertilized with iron, and carbon (non CO2), with intense (3-4 w/g) lighting-but the ferts and carbon were adjusted per the plants performance, and nothing else

i think you're right in that the wc's do seem to be counterproductive in removing some/alot of what we add to begin with, heh-but the argument could also be made that that happens w/respect to all of the calcium, etc., we add to reef tanks

however, i believe that the main reason for the huge wc's in the fertilizer nutz's tanks is for a CORRECTIVE purpose-which shouldn't be necessary, once you learn to read the plants themselves, and adjust dosages accordingly-like you would do with any terrestrial garden

 

[Anonymous]

Thanks Vitz - I appreciate the response.

i'd be doubtful and suspicious of anything written/said by barr- i think he's waaay out in left field on so many levels it's actually amusing

I've got to admit, it's very hard for me to take it seriously when he says light and not nutrient levels are the cause of algal outbreaks.

however, i believe that the main reason for the huge wc's in the fertilizer nutz's tanks is for a CORRECTIVE purpose-which shouldn't be necessary, once you learn to read the plants themselves, and adjust dosages accordingly-like you would do with any terrestrial garden

Pretty much what I was thinking. But no one who advocates these 50% weekly water changes SAYS it's for corrective purposes where the ferts are concerned. Then again, at least two of the loudest voices recommending heavy dosing and huge waterchanges sell dry fertilizers to hobbyists themselves.

most of the planted tanks i've done have been fertilized with iron, and carbon (non CO2),

Just iron and carbon, none of the other bottled mixes? And I assume you were using a substrate or substrate additive that had high nutrient levels?

I gather you used the liquid carbon additive they make, based on an old thread of yours, not one of the oddball electrolysis-based CO2 generators or anything, right? How well did that work for you, and on what size tank? I'm planning something in the 15-20 gallon range myself, but I'd like to grow a carpet of glossostigma or HC so I'm figuring from what I'm reading that carbon addition is going to be fairly critical. Just kind of up in the air still as to how I'm going to dose it. The liquid would be ideal for least headaches (if it'll work); otherwise I'll be looking at either yeast culturing or futzing with a pressurized tank.

 

[Anonymous]

i used the liquid additive 'excel' by seachem, on a 12 gallon bowfront, and the 'flourish' iron, as well as a very small amount of their flourish trace element addditive (though i don't think the trace was that critical)

i rely on fish for the rest of the nutrients

glosso will require a good bit of carbon, but with a small tank, it shouldn't be an (difficult to provide) issue

most of my larger planted tanks had laterite mixed in with flourite for a substrate-imo-the laterite was instrumental in the good results of my crypts and swords

 

[Anonymous]

glosso will require a good bit of carbon, but with a small tank, it shouldn't be an (difficult to provide) issue

That's my hope. I'd rather not have to muck with a pressurized system for a tank this small. Maybe I'll give the Excel a shot, possibly running in tandem with some DIY yeast at first to see how things go.

The plan is pretty simple, really - a glossostigma or HC carpet, a couple bunches of blyxa japonica , maybe something else in the back that's tall to hide equipment. Couple octos and a cory for clean up crew, and a small school of featherfin rainbows.

most of my larger planted tanks had laterite mixed in with flourite for a substrate

I'm figuring on using either Eco-Complete or the ADA line of soils... amazonia and tourmaline.

i used the liquid additive 'excel' by seachem, on a 12 gallon bowfront, and the 'flourish' iron, as well as a very small amount of their flourish trace element addditive (though i don't think the trace was that critical)

Sounds reasonable - much moreso than the other recommendations I've gotten.

Oh, stray question... any idea how much light floating plants like duckweed or salvinia -really- blocks? I've toyed with the idea of including them, but I'm not sure how practical it is from a lighting perspective. I'm planning to use a 4 x24w T5 fixture and don't know if they'll punch enough light through the layer of floating plants to suit the glosso/HC.

 

[Anonymous]

stay away from duckweed-it's the pita from hell-you'll never get rid of it once it's introduced, heh

salvinia and other floaters will block light - think of little pieces of cardboard floating on your tank and spreading -they also are very efficient nutrient uptakers (their roots are extremely fine with huge surface area)

 

[tazdevil]

I'm figuring on using either Eco-Complete or the ADA line of soils... amazonia and tourmaline.

FWIW, An original planted tank I had I used Eco-complete, and had hair algae from hell to deal with all the time. I changed from that to Flourite, and had some minor hair algae that went away on its own. I'm not going to say that A caused B to happen, it was my experience. I know plenty of people swear by Eco-complete and love it.

I also have a very high nitrate issue in the Tapwater, which does get R/ODI filtration, however, some still gets through.

I do not supplement with any other form of fertilization, and use the Hagen natural co2 system as the only supplement.

I probably don't change the water nearly as often as I should, however, I did add Rosy barbs when the hair algae became a problem (the second time) and they completely eliminated it. I think they are also eating
some of the plants.


The tank has : dwarf saggitaria, corkscrew val, anubias nana, ludwigia repens, anacharis, Alternanthera reineckii.

 

[gpodio]

Hi there cjdevito, I don't think we know each other but your question is very interesting to me. I have been keeping planted tanks for over 20 years and have seen the birth of many "new" methodologies, from PMDD, EI, PPS and the revived "El Natural" from Diana's book which really brings back some memories of my first dutch setups in the mid 80s. I think I may be able to shed a little light on your initial quesitons in regards to Tom's EI methodology...

First off let me say that I have tried all the above, including many of my own personalized methods. I have had success with all of them, none of them are "wrong", but they are tailored to different types of planted tanks, be it difference in growth speed, lighting or types of plants that prefer a certain environment...

That said, to really understand how the EI methodology came about we must consider the time it was conceived in. In essence it bases itself on the previously released Sears/Conlin PMDD paper. PMDD had a couple limitations, first off it was a method based on lower lit tanks where CO2 was optional at most, and only used in one of the many tanks used to test the methodology. It based it's algae-beating strategy on limitation of macros such as phosphates. It also based itself on maintaining certain levels of nutrients in the tank, requiring more testing than most people were happy to perform. As lighting increased so did deficiency related problems. We started to encounter deficiencies ranging from PO4 to CO2 and NO3, something that was practically unheard of with lower light levels. The EI changed a couple things with the PMDD, first off it added PO4, which to everyone's surprise didn't cause any algae problems. Second it added CO2 to sustain the growth rate dictated by the stronger lighting. Third, it did away with having to constantly test for residual nutrients by "resetting" levels for the most part by performing these large weekly water changes.

If you look back at the forums of just prior to the EI methodology, you will see that many newcommers (and some of us veterans) were battling algae and deficiency related problems as we followed the trend of "more light". The problem is that the number of nutrients important for plants are numerous, their chelated state varying, and testing for all of them can be difficult and time consuming. It's not quite as "Scientific" or "pre-determined" as it is in the reef world. His idea was to try and make a methodology that was easy for anyone to adopt and which gave good enough results for people to shift their efforts towards aquascaping more so than fighting algae or poor plant growth. His solution was to base one's fertilization on what is dosed rather than what is left behind from the previous doses, doing away with the need to run many tests. The 50% water change greatly resets most of the levels in the tank and his conservative dosing based solely on tank size and average tap water levels made testing a thing of the past and fertilizer doses a repetitive thing. Sure it's a big waste of ferts, it's also not as flexible accross various different types of tanks, but it allowed many people to grow healthy plants long before their experience allowed them to do so based on their own interpretation of the tank's progress. Ideally of course one would (should) start to personalize the initial methodology based on their individual tank and rate of growth, slowly evolving into whatever is ideal for you particular tank. But it certainly gave people that head start, it is easy to adopt with little experience and has helped many people including myself. A more recent alternative is the PPS, however that does entail testing which I am too lazy and busy to perform on all my tanks. Today I have a set methodology for each tank, but initially I do follow a slightly "bastardized" version of Tom's EI.

As for "competition" between plants and algae, we still kick this idea around with little conclusion. The fast growing tanks of today have certainly proven that a good healthy volume of plants will thrive over algae even in abundant conditions. We have tanks with PO4 levels in the 3-5ppm, nitrates around 20ppm, CO2 around 30-40ppm and yet no algae problems. We have even found a correlation between PO4 and certain algae, where raising PO4 levels can greatly help reduce it's growth rate... go figure! Tom and I have debated over this many times, I don't think he believes the "competitive" theory any more than I do. Personally, I think beyond a certain plant mass and speed of growth, the oxygen saturation we acchieve each day plays a greater role at oxidizing algae than anything else... but it's nothing more than one man's theory. I don't think anyone has had the last word on this topic yet, we can just go by what we observe in our tanks... I guess you can say we know more about "what works" than "why it works".

In your particular case, glosso seems to prefer CO2 but HC just loves Excel. Some plants just respond differently to it, a few hate it, some do OK and other go nuts with it. Here you can see the growth rate I acchieved with HC: (second from top)
http://www.gpodio.com/gallery_video.asp

The tank was just over 7WPG, a rich substrate, daily 10% water changes and 2x doses of excel were the only forms of nutrients. The tank was completely carpeted within the first 3 weeks. This was the only way I could get HC to grow as the fish in all my other tanks (ancistrus and loaches mostly) kept it from rooting in properly.

As for floating plants, I use them in all my newly established tanks and often keep some for the long term as well. Floaters have the huge advantage of being right under the light and having access to atmospheric CO2, meaning their growth rate is not limited by being submerged. I truely believe they help combat the initial and inevitable startup problems with filamentous and other forms of algae. Obviously, you must keep their numbers at bay, I remove floaters on a weekly basis. As long as they float around and not get stuck in one corner where they permanently shadow plants below them they cause me no problems. Obviosuly if the amount of lighting is barely acceptable for the plants you keep, floaters may not be a good idea. But if you plan for them in your choice of lighting, you should easily be able to keep them and grow plants below them.

One of my favorite duckweed moments: 8O
http://www.gpodio.com/gallery/scene12.jpg
http://www.gpodio.com/gallery/scene13.jpg

Right now I have tanks that range from 75% weekly water changes to 50% bi-yearly changes... different types of tanks, each with their pros and cons, but all working quite well. I don't have any rich substrate tanks up and running at the moment but when I decide to get back into crypts, lace plants and similar heavy rooters I wouldn't think twice about digging up some dirt in my back yard and doing the "dutch/Diana" thing all over again :wink:

Sorry to go on so long, obviously this is a topic I love to discuss

Regards
Giancarlo Podio

 

[Anonymous]

Gee I just use low light, sand, no ferts, no water changes, no filters.

And have 20-30 fish in a 10g for 6 years with only bi annual very minor algae cleanups.

So I guess it is just what one wants. In my case lotsa fish and plants with low maintenance.

 

[Anonymous]

Gee I just use low light, sand, no ferts, no water changes, no filters.

And have 20-30 fish in a 10g for 6 years with only bi annual very minor algae cleanups.

So I guess it is just what one wants. In my case lotsa fish and plants with low maintenance.

and yet you still keep ignoring the points made here about the way your tanks look :roll:

let's see you do a tank that even 1/2 approaches an aga website candidate-then you can talk :roll:

 

[Anonymous]

giancarlo

barr's problem is that he unequivocally states that light, and not nutrients, is the root cause of algae, when it's soooo plainly obvious, and proven, even! that the opposite is in fact the case

you can grow algae easily with high nutrients and low light levels, but it's exceedingly difficult to grow algae with low nutrients and high light levels-ergo, barr is blowing smoke up his OWN hiney, let alone what he's doing to noob's education form the get go

i think that not only is he basically ignorant by choice, he's propagating mis-information irresponsibly

i wonder why his site is 'closed to the general public' ?

 

[gpodio]

Gee I just use low light, sand, no ferts, no water changes, no filters.

And have 20-30 fish in a 10g for 6 years with only bi annual very minor algae cleanups.

So I guess it is just what one wants. In my case lotsa fish and plants with low maintenance.

Sure it is, it's up to you what you want. You're just following a different methodology for a completely different tank. Neither is right or wrong, nor "better", it depends on what you want. If you needed a fast growing tank to allow you to "aquascape" and tickle your artistic tallents then you'd likely be doing it differently too. For a relaxing, laid back living-room tank who's sole purpose is to look pretty, your tank is perfect.

 

[Anonymous]

Good morning, Giancarlo. Thank you for your post. No, I don't think we've run into each other before. Your post went quite a ways towards answering my initial questions, but it raises several new ones.

...
His solution was to base one's fertilization on what is dosed rather than what is left behind from the previous doses, doing away with the need to run many tests. The 50% water change greatly resets most of the levels in the tank and his conservative dosing based solely on tank size and average tap water levels made testing a thing of the past and fertilizer doses a repetitive thing. Sure it's a big waste of ferts, it's also not as flexible accross various different types of tanks, but it allowed many people to grow healthy plants long before their experience allowed them to do so based on their own interpretation of the tank's progress. Ideally of course one would (should) start to personalize the initial methodology based on their individual tank and rate of growth, slowly evolving into whatever is ideal for you particular tank.

Okay, that does explain the reasoning behind the heavy fert additions and the large frequent water changes. I've got to admit I don't think I personally care for this methodology, but at least I now know the reasoning behind it. Thank you.

One thing immediately bothers me, though. The idea behind the 50% weekly water changes is to ensure that the levels of dosed ferts never gets to twice the amount dosed in a single week, if my understanding is correct. However, it would seem there are at minimum three sources of nutrient input which would throw this out of equilibrium, and quickly.

1. Water input, both for topping off and for the water changes themselves. Few planted tank owners rely on RO or DI for their source water, and thus to a lesser or major degree nitrates, phosphates, etc will be introduced via the tap water itself.
2. Food input. Although not an issue in fishless tanks, any tank which is fed fish foods is receiving a large input of fertilizers in the form of fish food.
3. Substrates. All of the recommended substrates, from potting soil to the high end commercial products sold by ADA, are rich in organic fertilizers. All of these leach considerable amounts of nutrients into the water column.

How does a blanket dosing regimen take these three factors into account? Especially seeing as how wildly variable each of the three might be from one hobbyist, one aquarium, to another.

A more recent alternative is the PPS, however that does entail testing which I am too lazy and busy to perform on all my tanks.

The term PPS I'm not familiar with at all, I'm afraid. Can you elaborate?

As for "competition" between plants and algae, we still kick this idea around with little conclusion. The fast growing tanks of today have certainly proven that a good healthy volume of plants will thrive over algae even in abundant conditions. We have tanks with PO4 levels in the 3-5ppm, nitrates around 20ppm, CO2 around 30-40ppm and yet no algae problems.
...
Tom and I have debated over this many times, I don't think he believes the "competitive" theory any more than I do. Personally, I think beyond a certain plant mass and speed of growth, the oxygen saturation we acchieve each day plays a greater role at oxidizing algae than anything else... but it's nothing more than one man's theory. I don't think anyone has had the last word on this topic yet, we can just go by what we observe in our tanks...

Yet in saltwater tanks, where oxidation is not an issue because the biomass competing for items like phosphate is animal in origin, not plant, we can clearly demonstrate that such outcompetition takes place. Xenia, which I see you've kept as well, has always been a favorite method of nutrient export for me, as it does such a wonderful job of binding phosphate within it's tissues.

Still, we can agree to disagree on this. Irregardless of the base reason for why a large non-algal biomass works to prevent significant algal growth, it still works - which is the important thing

We have even found a correlation between PO4 and certain algae, where raising PO4 levels can greatly help reduce it's growth rate... go figure!

Coralline algae in the marine tank behaves in exactly the same way. Although in it's case, of course, the reason why is that high levels of phosphate inhibit the calcification process which it requires to grow. I would imagine that high phosphate levels could similarly impact a neccessary biological process required by various species of freshwater algae.

I guess you can say we know more about "what works" than "why it works".

Understood. I have difficulty with that, myself. The driving mantra of my time in reefkeeping has always been "if you don't understand how/why something works, it doesn't belong in your tank".

In your particular case, glosso seems to prefer CO2 but HC just loves Excel.

Thank you! I know it's a digression from the main thrust of this thread, but this is hugely helpful practical advice for what I'm planning to do and I appreciate it greatly.

As for floating plants, I use them in all my newly established tanks and often keep some for the long term as well. Floaters have the huge advantage of being right under the light and having access to atmospheric CO2, meaning their growth rate is not limited by being submerged. I truely believe they help combat the initial and inevitable startup problems with filamentous and other forms of algae.

This was my thought as well, still coming at things from a reef tank/ nutrient export perspective. I haven't been sure it translated across into a planted tank methodology, but I figured few things could beat duckweed for it's ability to bind nutrients.

Obviosuly if the amount of lighting is barely acceptable for the plants you keep, floaters may not be a good idea. But if you plan for them in your choice of lighting, you should easily be able to keep them and grow plants below them.

Can you provide anything along the lines of practical guidelines in this? For example, I'm planning 96w of T5 bulbs above a 15g or 20g tank. Is that such that I can manage floaters and an HC carpet, or would I be needing something more along the lines of a 175w halide for the job?

Sorry to go on so long, obviously this is a topic I love to discuss

Don't apologize, it was very helpful. I can't say I agree with all of what you wrote, but it went a very long way towards helping me understand the systems being discussed.

 

[gpodio]

giancarlo

barr's problem is that he unequivocally states that light, and not nutrients, is the root cause of algae, when it's soooo plainly obvious, and proven, even! that the opposite is in fact the case

Vitz, are you referring to a particular post of his? I have to admit this isn't his usual rant if you know what I mean. I'd like to see the post you are referring to. Usually Tom gives little importance to the type of light, he is the first to tell you to go to Home Depot and pick up a shop light... Perhaps he is talking about intensity, which would be correct as many people today buy ridiculously bright fixtures just because... they are brighter :roll:

But there are many wrong ideas and inaccurate conclusions out there in regards to nutrient levels and their impact on algae growth. My experience has told me that in high light/fast growing conditions, do what's right for the plants, not what's wrong for the algae, meaning no limitation what so ever. Make everything available to the plants and "somehow" they thrive and algae doesn't... Lower light tanks are different, but if we're discussing Tom's EI we're stricly talking "fast tanks".

you can grow algae easily with high nutrients and low light levels, but it's exceedingly difficult to grow algae with low nutrients and high light levels-ergo, barr is blowing smoke up his OWN hiney, let alone what he's doing to noob's education form the get go

Well I can't say I agree here. Low light tanks usually follow a lean diet while high light tanks require good nutrient levels. You have to understand how plants work, if just one element is missing and the plant depleats it's own stored supply of it, the entire process is halted and all nutrients become an eccess. It is only when plants have everything they need to thrive that they "outcompete" algae so to speak. Obviously that doesn't mean that you blindly throw ferts into such a tank, but I can assure you that if done properly this approach gives very good growth quality and still remains algae free.

IMO the "best" growth quality is in the medium light range with high nutrient substrates, however not at all a good option for an aquascaper who needs to prune and replant frequently...

i think that not only is he basically ignorant by choice, he's propagating mis-information irresponsibly

i wonder why his site is 'closed to the general public' ?

I agree, he is in secret communications with algae grazing extra terrestrials who's plans are to cover the planet with algae in order to make it suitable for their needs :twisted:

So he tried to make a buck online and then changed his mind, that's how I see it. His forum hasn't been closed to non-members in some time though, it's open to the public and membership is free... it's pretty much just another public forum now.

I think honestly if you were to give any one of these methods a proper chance you'd likely see that they do work when adopted correctly and used on the correct type of tank. Tom may be a little stubborn in regards to his own methods, but then again so am I, so are you and Bob, else you wouldn't be at each others throats all the time :wink:

 

[Anonymous]

giancarlo

barr's problem is that he unequivocally states that light, and not nutrients, is the root cause of algae, when it's soooo plainly obvious, and proven, even! that the opposite is in fact the case

Vitz, are you referring to a particular post of his? I have to admit this isn't his usual rant if you know what I mean. I'd like to see the post you are referring to. Usually Tom gives little importance to the type of light, he is the first to tell you to go to Home Depot and pick up a shop light... Perhaps he is talking about intensity, which would be correct as many people today buy ridiculously bright fixtures just because... they are brighter :roll:

But there are many wrong ideas and inaccurate conclusions out there in regards to nutrient levels and their impact on algae growth. My experience has told me that in high light/fast growing conditions, do what's right for the plants, not what's wrong for the algae, meaning no limitation what so ever. Make everything available to the plants and "somehow" they thrive and algae doesn't... Lower light tanks are different, but if we're discussing Tom's EI we're stricly talking "fast tanks".

you can grow algae easily with high nutrients and low light levels, but it's exceedingly difficult to grow algae with low nutrients and high light levels-ergo, barr is blowing smoke up his OWN hiney, let alone what he's doing to noob's education form the get go

Well I can't say I agree here. Low light tanks usually follow a lean diet while high light tanks require good nutrient levels. You have to understand how plants work, if just one element is missing and the plant depleats it's own stored supply of it, the entire process is halted and all nutrients become an eccess. It is only when plants have everything they need to thrive that they "outcompete" algae so to speak. Obviously that doesn't mean that you blindly throw ferts into such a tank, but I can assure you that if done properly this approach gives very good growth quality and still remains algae free.

IMO the "best" growth quality is in the medium light range with high nutrient substrates, however not at all a good option for an aquascaper who needs to prune and replant frequently...

i think that not only is he basically ignorant by choice, he's propagating mis-information irresponsibly

i wonder why his site is 'closed to the general public' ?

I agree, he is in secret communications with algae grazing extra terrestrials who's plans are to cover the planet with algae in order to make it suitable for their needs :twisted:

So he tried to make a buck online and then changed his mind, that's how I see it. His forum hasn't been closed to non-members in some time though, it's open to the public and membership is free... it's pretty much just another public forum now.

I think honestly if you were to give any one of these methods a proper chance you'd likely see that they do work when adopted correctly and used on the correct type of tank. Tom may be a little stubborn in regards to his own methods, but then again so am I, so are you and Bob, else you wouldn't be at each others throats all the time :wink:

beasle has no true 'methods' of which i've been made aware of, since he's been posting on this forum

all other things being equal-if nutrients are in good supply, and light is limited/low, some type of algae will grow (most higher plants will struggle)
if nutrients are low, but available, and light is low, some type of algae will grow (most higher plants will struggle)

if nutrients are low, and light is good-plants will still outcompete algae

if nutrients are high, and light is good-plants will outcompete algae

ergo...

So he tried to make a buck online and then changed his mind, that's how I see it. His forum hasn't been closed to non-members in some time though, it's open to the public and membership is free... it's pretty much just another public forum now.

er-not exactly

Vitz, are you referring to a particular post of his?

i'm refering to what was a publicly viewable article on his 'old' site, a year or two back

Obviously that doesn't mean that you blindly throw ferts into such a tank, but I can assure you that if done properly this approach gives very good growth quality and still remains algae free.

that's pretty much his entire philosophy-blindly overfertilizing a tank, and then assuming a water change will then balance it out (an outright fallacy!).

 

[gpodio]

...
One thing immediately bothers me, though. The idea behind the 50% weekly water changes is to ensure that the levels of dosed ferts never gets to twice the amount dosed in a single week, if my understanding is correct. However, it would seem there are at minimum three sources of nutrient input which would throw this out of equilibrium, and quickly.

1. Water input, both for topping off and for the water changes themselves. Few planted tank owners rely on RO or DI for their source water, and thus to a lesser or major degree nitrates, phosphates, etc will be introduced via the tap water itself.
2. Food input. Although not an issue in fishless tanks, any tank which is fed fish foods is receiving a large input of fertilizers in the form of fish food.
3. Substrates. All of the recommended substrates, from potting soil to the high end commercial products sold by ADA, are rich in organic fertilizers. All of these leach considerable amounts of nutrients into the water column.

How does a blanket dosing regimen take these three factors into account? Especially seeing as how wildly variable each of the three might be from one hobbyist, one aquarium, to another.

Actually, the water changes address these directly. We in the US are quite lucky with tap water quality and for the most part, it contains nutrient levels that are well below those required for fast growing tanks. The frequent large water changes assures that the water in the tank remains relatively close to original tap water conditions prior to dosing. If we stop the changes, we must pull out testing equipment to monitor any accumulation due to the three items you pointed out. When you're changing 50% weekly, accumulation due to top-off, feedings and doses becomes quite diluted. As for the #3, Tom's EI was based on an inert substrate such as Flourite. Using ADA, Eco-Complete, Soil or other rich substrates usually changes things and forces one to go by test results and visual results for the first few months. Tom's method does not include substrate fertilization nor the use of rich substrates. This is where Tom and I have debated on things greatly, I am still stuck on rich substrates and therefore adjust my fertilization accordingly.

The term PPS I'm not familiar with at all, I'm afraid. Can you elaborate?

Perpetual Preservation System:
http://www.aquaticplantcentral.com/foru ... s-feedback

Yet in saltwater tanks, where oxidation is not an issue because the biomass competing for items like phosphate is animal in origin, not plant, we can clearly demonstrate that such outcompetition takes place. Xenia, which I see you've kept as well, has always been a favorite method of nutrient export for me, as it does such a wonderful job of binding phosphate within it's tissues.

Still, we can agree to disagree on this. Irregardless of the base reason for why a large non-algal biomass works to prevent significant algal growth, it still works - which is the important thing

Yep, and we must also keep in consideration the oxygen levels achieved by fast growing planted tanks, they are above anything a reef tank can master up... Plants emit pure O2, they can saturate the water within 4 hours of photosynthesis. I currently have a test under way using O2 tanks to saturate the water artificially, this may help me understand better what role, if any, oxygen plays in the "competition".

Coralline algae in the marine tank behaves in exactly the same way. Although in it's case, of course, the reason why is that high levels of phosphate inhibit the calcification process which it requires to grow. I would imagine that high phosphate levels could similarly impact a neccessary biological process required by various species of freshwater algae.

Indeed this is quite possibly what is happening in FW tanks too as the algae that is effected in such a manner is mostly green and black spot algae.

I guess you can say we know more about "what works" than "why it works".

Understood. I have difficulty with that, myself. The driving mantra of my time in reefkeeping has always been "if you don't understand how/why something works, it doesn't belong in your tank".

I'm sure there are many things that go on we don't understand. But if we know something works well I don't see too much danger in doing it, it's how we often find out the "why"

As for floating plants, I use them in all my newly established tanks and often keep some for the long term as well. Floaters have the huge advantage of being right under the light and having access to atmospheric CO2, meaning their growth rate is not limited by being submerged. I truely believe they help combat the initial and inevitable startup problems with filamentous and other forms of algae.

This was my thought as well, still coming at things from a reef tank/ nutrient export perspective. I haven't been sure it translated across into a planted tank methodology, but I figured few things could beat duckweed for it's ability to bind nutrients.

I find any kind of flater to be very useful at first. It often takes a couple months before the substrate is mature and plants have rooted well enough to concentrate most of the energy to foliage development, at which time floaters start to compete for light and nutrients and become less important overall.

Obviosuly if the amount of lighting is barely acceptable for the plants you keep, floaters may not be a good idea. But if you plan for them in your choice of lighting, you should easily be able to keep them and grow plants below them.

Can you provide anything along the lines of practical guidelines in this? For example, I'm planning 96w of T5 bulbs above a 15g or 20g tank. Is that such that I can manage floaters and an HC carpet, or would I be needing something more along the lines of a 175w halide for the job?

Wow, at those levels you will quickly become a fan a Tom's EI :wink: Seriously, 3-4WPG is all that is needed to grow the most demanding of plants. Above these levels usually takes some dedication if you know what I mean... I also feel that PCs will give you better bulbs to choose from, unfortunately T5 choices are still pretty slim. Either way at these light intensities you should not have any problems keeping floaters and carpeting plants, just keep the floaters in check by weekly removal.

Not sure if these are of any use to you but just to point out how pretty good results can be had by very different approaches, this is a typical EI driven tank, it actually gets 75% water changes and fertilizers are dosed automatically by the hour. Quantities of ferts here are very high here, above those generally suggested by Tom:

(55g, 3.3WPG, 30ppm CO2)

On the flip side, here's my bi-yearly water change tank, it's a 90g with 1WPG, no CO2 and a rich substrate:

Last one, 2.5g with 18W of light. Daily 2cup water changes and yeast driven CO2. No other ferts, substrate is super rich and something you rarely want to disturb...

Esthetically I feel they are all very nice, but the second would struggle to grow most of the plants in the first. The top tank is in my living room where I can baby it daily. The second is in my wife's office which I only see on occasions...

Hope that helps

 

[gpodio]

if nutrients are low, and light is good-plants will still outcompete algae

if nutrients are high, and light is good-plants will outcompete algae

Yes, but in the first instance under fast growing conditions plants will usually start to show simptoms of deficiencies as uptake rates of certain elements drop. Osmotic pressure plays a great role in uptake rates and this is the reason why for example 5ppm NO3 is not as efficient as 10ppm.

Obviously that doesn't mean that you blindly throw ferts into such a tank, but I can assure you that if done properly this approach gives very good growth quality and still remains algae free.

that's pretty much his entire philosophy-blindly overfertilizing a tank, and then assuming a water change will then balance it out (an outright fallacy!).

Are you sure you don't have any axes to grind with Tom? I don't personally feel he does anything blindly, he may do it "stubbornly" but he does know what he's talking about. I too don't agree with everything he says, but I do recognize him for having made some important steps at a time when they were against popular beliefs. If you go back to the original EI article and take it as a starting point I think you too would find it works. Obviously anyone following the same schedule for years without any modification has learned nothing from their tank. One should be able over time to get a feel for their own tank and start to cut back on water changes and wasted ferts, following the tank's own trend moreso than any one particular fertilization regiem.

http://www.aquatic-plants.org/articles/ ... ndex1.html

Keep an open mind, IMO there are too many people doing this and having wonderful results to call him outright insane... I tried it, it worked for me and I later moved on by modifying it to my own needs... it came at a great time for me too as I was just entering the high-light scene from many years of low light, rich substrate tanks.

If you are truely honest about this and open to learning more about it, listening to other people's experiences in regards, I strongly suggest you visit a dedicated plant forum such as APC or APD. You will get comments from both ends, pro and against. Here I fear it will turn into a ping-pong match between the 4 of us :wink: