question for the microbiologist

[reefkprZ]

BTW I do have a day job that keeps me very busy, so if you do want an answer specific from me you would have to display patience or PM me directly.

I do understand that you have a job that keeps you busy. I figured anyone would understand that I wasnt pressing when I stated "I'm not in a rush, I'm just curious" the other parts of my posts were to try and get other members involved.
you seem a little offended, and I am sorry if you are, though absolutly no offense was intended and I dont know how I did it.

 

[ShaunW]

you seem a little offended, and I am sorry if you are, though absolutly no offense was intended and I dont know how I did it.

I am not offended at all, . Please don't take that away from my post. I am really happy to discuss microbiology.

My post above is just stating the fact that during the day I do academic research (microbiology) at Cornell University and often find it difficult to find the time to get on MR.

 

[ShaunW]

I ran an unnofficial/very unscientific expiriment some months ago to see if I could visually notice a difference in my tank from week to week while running my skimmer on one week and off the next. in the corals I did not notice ANy difference that I could pick out. the only visible difference was my front glass seemed to aquire the "film of obscurity" quicker by about half a day to a day towards the end of the skimmerless week. I would guess due to a slow build up of available phosphates to be consumed.

I then ran skimmer-less for an entire month (due to a skimmer malfunction that I was to lazy to repair). I did not notice any difference in the appearance of my tank and inhabitants other than the aforementioned "film of obscurity" having to be cleared every day instead of every 3-4 days at the end of the month.

I am not sure how old you tank is, but once a reef tank has cycled with nitrite undetectable, the bacterial population has become established. From there it will obviously fluctuate with different species gaining greater space and venturing into new niches while others will lose out. But in general once the establishment has been made and the conditions within stabilized (temp, light cycle, nutrients, etc) the population will also stabilize. So my point is that I don't think that running skimmerless or not will make very little difference with all things being equal (no changes in nutrients). Now if you were to run skimmerless and provide a C-source or have a nitrate or phosphate spike then the effects would be different.

The interesting question is how long does it take and really how dynamic is the bacterial population over time? My belief is that it doesn't stabilize completely until the tank is really mature, i.e. more than 2 years old and much of the surface area within is established with either coral or bacterial biofilms. This is why "old" tanks are always more healthy.

 

[ShaunW]

I posted this elsewhere concerning SPS health, but in terms of bacterial population dynamics and flux the Redfield ratio IMO affects it greatly. Especially within an aquarium, since nutrient conditions can change rapidly.

http://www.manhattanreefs.com/forum/advanced-reefs/17828-coloring-up-sps-8.html

Many of the quick fixes in the hobby such as vodka dosing and amino acid additions are really just manual adjustment to the inorganic ratio with the hope of changing the organic.

I realize that this thread is about bacterial removal by skimmers, but everything is related IMO and talking about one thing can't be done without discussing the whole system from a bacterial point of view.

 

[reefkprZ]

I agree, I want to focus on the organic portion not nescesarily just bacteria, but as needs may demand we delve into other subjects to clarify or make a broader veiw of the subject. I have a pretty comprehensive list of what elements a skimmer is capable of removing in trace and large amounts, but it seems the organic side is still pretty vague even among experts. obviously individual tanks with their own developed systems will have different availabilities of various strains of organism.

I wonder if running a skimmer may actually dictate (in part) weather ceartain species of microfauna or bacteria dominate, if one species is very hardy but very prone to getting skimmed, its not going to fare very well in a heavily skimmed tank, and a maybe weaker strand may come out dominant by it resistance to skimming, or maybe it would take the "skimm prone" species longer to fully establish. (yes these are the weird little things that keep me up at night)

I have to admit my strengths lie mostly in coral propagation, not bacterial strains other than the occasional mention of the petri dish that our corals are with vibrio and pseudomonas and such on them to make others aware of the very real caution they should use when handeling corals. I really know very little solid about the bacteria that are in our tanks. I am familiar with the nitrogen cycle etc.

 

[reefkprZ]

The interesting question is how long does it take and really how dynamic is the bacterial population over time? My belief is that it doesn't stabilize completely until the tank is really mature, i.e. more than 2 years old and much of the surface area within is established with either coral or bacterial biofilms. This is why "old" tanks are always more healthy.

I would have to say at minimum it takes about a year of very little change for a tank to become mature. a tank cant really fully balance out untill things stop changing dramaticaly. I.E. once you've reached the full amount of LR your going to add maturing really begins, as long as you keep building up LR your adding more area, more bacterial strains, microfauna, macrofauna, microalgae, macroalgaes etc this all has to balance out into dominant populations. and like you said after about 2 years a tank can generally considered mature because the most dramatic changes usually happen with the first year as well as nutrient influx and export becomes habitual or, maybe better said the tanks owner falls into a semi-ritual of habit for the care of their tank. interest in tanks tend to wax or wane depending on the person after a year a person generally falls into about the habits they are going to keep for the duration (this is a generalization of course), so once things all hit an even stride, the persons feeding habits, fish population (bioload), waterchange habits, equipment maintinence, a tank truly matures obviously its maturing the whole time, but once a tank truly begins to stabilize, the maturation process accellerates.

honestly I think overall the dynamics of bacteria diminishes over time as well as biodiversity of microfauna, this is one reason I have always kept the habit of replacing one large rock every couple of months to keep introducing new populations of microfauna, bacteria etc, to keep my biodiversity higher even if only for a short time. As the strongest tend to survive, the strongest may not be the most efficient detritivors, but simply the hardiest.

thanks for providing those links. I tend to research the heck right out of any new information I find, unfortunatly a lot of the info I want is under lock and key at research institutes and constantly run into brick walls when i find the info I want is going to cost 14$ just to read an article that may or may not actually be what I am looking for.

 

[ShaunW]

I have a pretty comprehensive list of what elements a skimmer is capable of removing in trace and large amounts, but it seems the organic side is still pretty vague even among experts. obviously individual tanks with their own developed systems will have different availabilities of various strains of organism.

Could you list out what you have found? other than this info below?
http://www.reefkeeping.com/issues/2002-12/rs/feature/index.php

I wonder if running a skimmer may actually dictate (in part) weather ceartain species of microfauna or bacteria dominate, if one species is very hardy but very prone to getting skimmed, its not going to fare very well in a heavily skimmed tank, and a maybe weaker strand may come out dominant by it resistance to skimming, or maybe it would take the "skimm prone" species longer to fully establish. (yes these are the weird little things that keep me up at night)

My personal belief, and since nobody knows it is just speculation, is that bacteria don't get removed by skimmers as efficiently as aquarists believe. They are neutrally charged, hydrophilic and small (1 micron). Since foam fractionation are most efficient at removing charged, amphipathic and/or hydrophobic molecules, bacteria not being this way would not be easily removed.

 

[ShaunW]

honestly I think overall the dynamics of bacteria diminishes over time as well as biodiversity of microfauna, this is one reason I have always kept the habit of replacing one large rock every couple of months to keep introducing new populations of microfauna, bacteria etc, to keep my biodiversity higher even if only for a short time. As the strongest tend to survive, the strongest may not be the most efficient detritivors, but simply the hardiest.

I actually believe the opposite. Once the tank is established doesn't necessarily mean the the total bacterial population isn't changing dynamically over time.

Let talk about a reef tank that has a deep sand bed, live rock that isn't removed or added too, 2 years old, mixed reef with SPS, LPS, zoos and xenia. After two years the DSB will be established with Facultative anaerobes and strict anaerobic bacteria. Nitrate will start to be released to the system and the DSB is converting it to nitrogen gas. In terms of bacteria population, it will flux according to the available nutrients. The greatest restriction on this flux is surface area for bacteria to attach too. However, bacteria have relationships with corals. SPS corals have more bacteria per unit volume than that of the water column in the wild. Therefore the coral mass represents a HUGE source of bacterial activity and mass and can IMO substitute for even a DSB in nitrate recycling if enough SPS corals are present.

So as the aquarium grows in terms of corals, the bacterial population itself is also going to grow.

thanks for providing those links. I tend to research the heck right out of any new information I find, unfortunatly a lot of the info I want is under lock and key at research institutes and constantly run into brick walls when i find the info I want is going to cost 14$ just to read an article that may or may not actually be what I am looking for.

My pleasure, .

 

[reefkprZ]

I think I misspoke when i said dynamics of bacteria diminishes.

I wasnt implying that bacterial numbers diminish, as you said the numbers wax and wane due to available nutrients. I was trying to say that possibly diversification diminishes, out of 24,000 (random number) strains of bacteria in one tank after say two years the strongest 20,000 will still be there while the weakest 4,000 will have died out being overtaken by the stronger strains. a DSb in a reef will of course take longer to mature as it has more surface area overall to colonize as well as differing environments. same thing with microfauna say, tiger amphipods, they corner an ceartain ecological nich in our tanks a weaker amphipod introduced at the same time may compete for a while but due to standard fluctuations in our tanks as well as competition from the tiger amphipods ends up dying out completly.

IE say in a fish tank you put two gold fish (bacterial strain a) and two guppies (bacterial strain b). at first neither really dominates but the goldfish being hardier has a better chance at survival, while the guppies can out breed the goldfish. eventually the gold fish may be the only fish in the tank due to its ability to outgrow and consume the guppy no matter how many babies it has. see what I'm saying.

or am i way off base here, and bacterial strains keep diversifying over time? (this is the type of info I am really looking for)

 

[ShaunW]

I think I misspoke when i said dynamics of bacteria diminishes.

I wasnt implying that bacterial numbers diminish, as you said the numbers wax and wane due to available nutrients. I was trying to say that possibly diversification diminishes, out of 24,000 (random number) strains of bacteria in one tank after say two years the strongest 20,000 will still be there while the weakest 4,000 will have died out being overtaken by the stronger strains. a DSb in a reef will of course take longer to mature as it has more surface area overall to colonize as well as differing environments. same thing with microfauna say, tiger amphipods, they corner an ceartain ecological nich in our tanks a weaker amphipod introduced at the same time may compete for a while but due to standard fluctuations in our tanks as well as competition from the tiger amphipods ends up dying out completly.

IE say in a fish tank you put two gold fish (bacterial strain a) and two guppies (bacterial strain b). at first neither really dominates but the goldfish being hardier has a better chance at survival, while the guppies can out breed the goldfish. eventually the gold fish may be the only fish in the tank due to its ability to outgrow and consume the guppy no matter how many babies it has. see what I'm saying.

or am i way off base here, and bacterial strains keep diversifying over time? (this is the type of info I am really looking for)

Without addition, the bacterial strains are not going to keep diversifying over time since what is present is related to the additions made, i.e. bacteria aren't going to spontaneously form. But the bacterial diversification is immense to begin with and the different ecological niches within a reef tanks are diverse. Each niche will probably have, in general, a dominate strain that would take over, however bacterial interrelationships are possible. You can have large communities of diverse bacterial living in harmony/equilibrium within a single niche. These communities would be so interrelated that individual strain extinction would not occur without crashing the whole community, DSB's communities immediately come to mind.

Individual bacterial species can enter stationary phase also and can exist in this non-replicative state for years. Take cynanobacteria for example. Most tanks undergo a cynanobacterial outbreak at some point and then it resolves. Did the bacteria die completely? the answer is NO. If you were to add sugar to even the most mature tank that has not seen any cyanobacteria for years, you would almost certainly get a re-amplification of cynanobacterial numbers immediately.

When you say that bacterial species will die off and that is bad (hope I am interpreting your thoughts properly here) the key question is: bad for whom or what? In terms of total bacterial influence on the entire ecosystem's nutrient recycling it doesn't matter, since most Facultative anaerobic bacteria can utilize carbon, convert nitrate to nitrogen anaerobically, and can live aerobically to convert ammonia stepwise to nitrate. They have the enzymes to perform all these metabolic functions, Pseudomonas and Mycobacteria are two such genus .

Other bacteria are "farmed" by SPS, attached to SPS mucus, and consumed for energy. Their numbers would be lineally equal to the SPS mass.

SPS symbiotic bacteria will be so isolated within their niche that they would only die off if the living coral host dies.

 

[reefkprZ]

your pretty much right on with what I was thinking except I didn't mean to imply the particular strains that didnt wind up dominant dying off was bad. I was more thinking that they may more efficient than a more dominant strain.

After hearing you spell it out for me, about it not really mattering which strain/s dominate because your cycle continues uninterrupted, and the system balances various strains reaching equilibrium and co-existing, the loss of a few strains or the couple strains going dormant wont really make a difference.

Its pretty much the conclusion I think I would have wound up with on my own. It has definatly been helpful to discuss this with you as way of confirming and disavowing ceartain thoughts that may have taken me many more months to hash through on my own while sifting through "myth-information" and trying to sort fact from fiction.

I have to say no matter how long I am in this hobby I relearn everyday how much more there is to learn. Thanks for taking the time to hash through this a bit with me.

Now about skimmers, in your opinion, when running a light bioload on a full blown reef thats well established, do you think they are worth the loss in trace elements that we fight so hard to maintain? Just a parting thought for the night, i have to go watch a movie with the future wife now.

 

[ShaunW]

Now about skimmers, in your opinion, when running a light bioload on a full blown reef thats well established, do you think they are worth the loss in trace elements that we fight so hard to maintain? Just a parting thought for the night, i have to go watch a movie with the future wife now.

THANKS! I am enjoying thinking about these things also.

Rethinking about the bacteria and skimmer question has made me figure out a fool proof way to answer the question whether skimmers remove bacteria and how efficiently they do it.

Without a doubt a skimmer is a valuable tool. I wouldn't run a reef tank without one. It is just too hard to regulate the input of nutrients to the utilization of nutrients by the system. Aquarists will always provide too much nutrients. Organic waste need to be removed, and there is no better way than foam fractionation. I am a big fan of water changes, on my reef I do 40% changes once a month, restoring trace elements.

Why? are you thinking about running skimmerless? because doing so would make excessive nutrient export much more difficult than not running a skimmer.

 

[clownlover]

i have to say that i run what i think is very light skimming now ( a remora on a 125G). i used to skim heavier but same thign happend to me, my skimmer broke and i was reading bout alot of people going skimmerless so i decided to try it. shaun is def right as far as exporting of excess nutrients but i do think my corals are "happier". pretty much everything in my tank is splitting / growing like crazy (i dont have sps though) although i do have to say that i have to watch how i feed and the lighting. it seems that running my tank the way i do it is more sensitive to changes, i.e. i recently added 1.5 hours onto my light cycle and it resulted in an algae bloom. when i ran a better skimmer that never happend, i used to play with photoperoids all the time. i guess you have to do what works for you in the end.

shaun, the tanks u did the plankton analysis on, did they feed phtyo to their tanks? if no, would that make a difference if they did u think?

 

[reefkprZ]

Why? are you thinking about running skimmerless? because doing so would make excessive nutrient export much more difficult than not running a skimmer.

a little side info on my tank:75g DT 30g sump 150lbs LR ssb display dsb sump, age 1 year 3 months since last move, but total tank age is about 3 years. skimmer 220g capacity, 5 types macro algae in sump. 440w VHOlighting 14hour on 10 off cycle

I'm definatly not considering going skimmerless, my feeding habits wont allow it even with my 25% waterchanges once a week and 50% once a month. I feed my tanks 5-7 times a day of various food. (there is more fish/coral coral food in my feezer and in my fish closet than most people own peole food) I firmly believe a lot of the corals in our systems are malnourished/underfed due to our inability to properly export the by products, true rapid growth can only be acheived by providing the proper diet for all these critters, damn hard to acheive when the by products of half of what they need for optimal growth would crash most systems because we cant get rid of the waste/unconsumed foods before it breaks down, this is where having diverse microfauna and my insane waterchange ritual as well as far overskimming my tank comes into play.

Basicly the whole basis of the conversation was on the fact that I WAY over skim and was wondering if I was doing detriment to ceartain populations of microfauna and bacteria by way overskimming, but the overall conclusion I have drawn is any detriment is negligable compared to the benifit of removing excess micro foods and waste before they break down, and contribute to pollution.

I just like hearing other peoples thoughts on similar subjects who have many years expirience, its easy for a newer hobbyest to say "skimmers are good" but when asked why you get the standard answer "because they are, they remove protiens" probably 70% of the hobbyest in their first year dont realize skimmers are exceedingly efficient at removing calcium too (among other elements), which is one of the elements we strive to maintain, often with difficulty when running a heavy scleractinian or clam dominated reef.

I have considered adding an algal scrubber, and an (this one will make a few people cringe) aiptasia race way filter thats UV sterilized on the output. so i can increase my feeding even more. my color and growth rates already are far beyond what most peole around here get. I have seen my frags after 6-8 months in other peoles tanks they dont look as good or seem to grow as fast for other people. there are some exceptions about maintaining color, but often the difference is very clear.

there is a tank nearby (newtoit knows the tank I speak of) it has 2x250w halides, in thory that lighting should be better than my 440w vho , all his SPS brown out, I bought an ugly brown acropora from him and its now a bright green highlighted purple. this of course hinges on many factors, good light bulbs, proper nutrient levels, proper trace etc. but within 2 months the corals turn around is mindblowing.

often peole who try to mimic my feeding habits or even feed once a day end up with horrible algae problems and I have no nuisance algae to speak of (what I am stating here is that my grazer crew can easily handle the growth of algaes in my display, not that it doesnt form). by feed my tank i dont mean feed my fish 5-7 times a day, I am feeding lots of micro foods, cyclops, dapnhia, home made foods, several algae foods, and so on rotating what gets fed to ensure if something doesnt utilize a ceartain food it doesnt have to wait long to get one it can.

free floating bacteria is also a food I want available to my corals so if skimming is a serious detriment to free flating bacteria I would consider, shutting down my skimmer for one day a week then kicking up the sand bed to send bacteria into the water column to make the bacteria available for the corals that consume it. before restarting the skimmer. (now this is again where your opinion really makes a difference for me) I have no way of guaging or knowing how much the overskim capacity diminishes the free floating bacterial levels in the tanks overall volume, if you were to say its most likley negligable I would continue to leave my skimmer running while I kick up my sand bed, if you thought that it reall cut down on the available bacteria I would probably shut my skimmer down 50% of the time when i was kicking up my sand bed. I stirr up my sand bed to release detritus for filtration too, so I would let it skim every other time I stirr my sand bed.

what are your thoughts on that?

 

[jhale]

reefkprZ, you stir up your DSB? I was always under the impression one should never touch a DSB.

When you say that you "WAY over skim" how do you know it's too much?
From your description of feeding it sounds like you need a larger skimmer.
I'm happy to read your feeding your tank, so many reefers tend to starve their tanks to try to control algae. I follow a similar feeding schedule and have a rather large skimmer for my tank now. It's my opinion that you can't over skim a tank. This is based on using a normal sized skimmer. Of course if your skimmer holds 10X the volume of your tank water, over skimming may apply

I would not worry about a skimmer removing trace elements. I think the trace elements are used up rather quickly by the coral in the tank. Finding a good brand of additives and sticking to a dosing regimen is just part of feeding the tank.

There are some great tanks with no skimmers, but they employ other methods of nutrient removal. Your algae scrubber idea could work, but you would have to size it appropriately, the larger the better. The idea of using aiptasia to filter the water has always been interesting, but who has done research as to how many aiptasia you need? I had a huge aiptasia problem in my system, I can't say I saw a decrease in water quality when I finally eradicated them. I think you would need a massive amount of them to make a dent compared to what a decent skimmer can do. If you like I'll be happy to supply you with some starter aiptasia, I believe there are still some lurking in my sump

 

[reefkprZ]

no I dont touch my DSB, I leave that to my critters to maintain. in my display the SSB I stir constantly to feed my corals and re-suspend detritus.

honestly by the term "way overskim" I just mean use a larger than rated skimmer and skim fairly wet. I dont think its actually ODing on skimming. its just an expression. kind of as a means of comparison to those who get the exact size for their tank (wich I think companies overestimate the capacities for their products any how).

I think you would need a massive amount of them to make a dent compared to what a decent skimmer can do.

yup picture a race way filter with 12 feet of raceway (4 feet by three turns with three surfaces in each pass) with egg crate "barriers" every 4 inches along the lengths(perpendicular to the side walls), every surface completly covered with aiptasia, that would be thousands of aip and millions of stinging fronds to capture particles. I would suggest that this would be one efficient means of capturing any organic particles to float through.

 

[clownlover]

i agree. aiptasia is probably not the way to go and it will be hard to keep it out of ur display. i think people use xenia for this aswell and it might be a better choice. about corals picking up the trace elements before the skimmer, i dont know. to be sure i shut my skimmer off for a bit when i dose ( i dont dose often though). but i have to say i dont do many water changes. once a month 10% or so. i have a dentritrator on my system, as well as a uv steralizer a tiny fuge and plenty of live rock. i like the natural approach i think.

 

[jhale]

I see, sorry I thought the DSB was in the display. stirring a SSB to clean it is cool.

It would be interesting to see the results from a biological Aiptasia filter. If you attempt it please track the results. I imagine after a year you would see a marked difference.

Perhaps an algae scrubber in tandem with and Aiptasia Nutrient Neutralizer would be a good combo. Throw in an area for cryptic sponges and your all set.

 

[reefkprZ]

i agree. aiptasia is probably not the way to go and it will be hard to keep it out of ur display. i think people use xenia for this aswell and it might be a better choice. about corals picking up the trace elements before the skimmer, i dont know. to be sure i shut my skimmer off for a bit when i dose ( i dont dose often though). but i have to say i dont do many water changes. once a month 10% or so. i have a dentritrator on my system, as well as a uv steralizer a tiny fuge and plenty of live rock. i like the natural approach i think.

people who use xenia use it to absorb dissolved nitrogens in situ, I want to use aip to capture particles before they breakdown into soluble components.

the way to prevent it spreading back into the display would be with a very HIGH powered UV on the return line at a very slow rate of flow therefore killing any cells or offspring that could cause an infestation in the tank.

I'm obviously going to have to do some research to figure out how much exposure to UV it will take to completly eliminate the risk of it spreading back into the tank.

aip as a filtration is not a novel Idea I believe Anthony Calfo mentions it in one of his books (at least I think it was Calfo I'll double check that I dont want to misquote) let me check my reference books and I'll get back on that.

 

[reefkprZ]

OK it was Anthony Calfo that I first heard it from (wheather he originated the idea or not I dont know)

Page 38 in the book: "Book of coral propagation volume 1 version 1.0" shows an image of nutrient scrubbing raceway, and on the following page he explains how to use aiptasia as a natural "scrubber" as they are voracious filter feeders and would be a great method of cleaning for tanks that have high input of foods such as baby brine rotifers and other microfoods. I'll do a direct quote from the book here

Anthony Calfo: The book of coral propagation, volume one, version 1.0
"Unwanted populations of Aiptasia that grow in display aquaria can be problematic as they compete for food and space and may injure other invertabretes with their stinging tentacles. In a remote downstream vessel, however, they may perform as an efficient living mechanical filter"

I have been mulling this idea over for well over a year and am not about to run blind into a method that will plauge my display with a nuiscance.