I'm using a cpr bakpak2r on my 70gal system. Yes i know it is underated for a 70g but its better then no skimmer at all! Although there is waste collecting in the collection cup I cannot determine if the skimmer is working to its potential. There is no sludge in the cup it appears as dirty water maybe dish water but i cant determine if its skimming effectively. I changed the powerhead from rio600 to a rio800 and there is a greater amount of waste collecting in the cup about the same consistancy in color as tproduced when using the rio600. Would it be beneficial to drop a air stone in the skimmer? Are micro bubbles the key to good skimming? Is it good to keep the SG up for effective skimming? What works for you, lets hear it...
SEcret to good skimming??
- Thread starter PicassoTrigger
- Start date
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote
Ok so maybe i was a bit hard on you earlier, and you obviously want this thing to work so i can tell you how i would do it, if you like.
Basically you have too many fish, there is no debate here, its a biological and physiological fact. This means either a bigger tank, with a skimmer to match. Or your going to have to trim back on your stock.
The fish you have chosen are probably the most unsuitable species to over-stock with only compounding eventual problems. This is primarily due to the eating habits of your fish. They are all incredibly messy, and produce a large ammount of waste while both eating and digesting.
Im betting the reason you have the two hermits is to over come this problem by having some sort of clean up crew. And beleave me with a tank like yours you will need it. Serpent stars will also help with this, and providing you have a suitable sand bed (3"-4" inches of Oolitic grade arragonite sand) a tiger tail cucumber or a queen conch would probably help a little too.
Just so you know your total fish length should be about 17 inches of fish. So, firstly get rid of the tang, as that requires a minimum of around 100 - 150 gallons due to swimming requirements.
Now bearing in mind that these calculations are for smaller community fish, and not the hulking beef cakes you have. I would stick with two of the big-uns. But admitadly they are small at present, but will grow very fast. So i guess you have a while before you have to start chosing your favorate two. I think the Volatan and one of the triggers would give a little variety in your inhabitants. Plus the lion wont swim half as much as any of the triggers leaving more swiming space.
You can wait till all your fish are arround 5 inches, then take out whichever trigger you dont want to keep, or get a bigger tank of course. But IMO the tang defenately has to go.
The skimmer is going to be very important to you because these guys are so messy. I really think that the little Back Pack is doing nothing. Beleave me there is skimmate sludge waiting in your system to come out, your skimmer just cant pull it. And this can be evident in the micro algal growth you may be expiriencing.
If you can set up a sump then all the better, but you may have overflow problems seen as the tank cant be drilled in-situ. Hang on skimmers arn't so bad, but you have messy fish so you need some power in that department.
With the back pack, id take an airstone and drop that in to add some bubbles, and remove the venturi. You can experiment allot with the setup so dont be afriad to try. The venturi's alone are very difficult to get a decent bubble size out of, which is why i wouldn't use a conventional venturi skimmer without some sort of needle wheel. HSA (High speed aspirated) skimmers are Venturi's but slightly better as induction is more effective creating a better air/water mix.
The Lime wood airstones are great at creating the correct bubble size, but need to be replaced periodically. You will know when because the bubbles will be much larger and the skimmate as you currently describe like dirty dish water. In addition to the limewood air stone you will need an air pump to run this. Go above the requirements presented by the airstone, allowing you to "throttle back" on the pump giving increased controll over the Air/Water mix. You will get much better at gaugeing this as the skimmte production increases.
The main principles are as follows:
Mix is too wet, I.E. like dishwasher liquid. Basically your using too much air. This is either pushing water directly into the collection cup, or foaming too rapidly taking too much water with the skimmate. So you end up with a mixture thats not thick and sludgy. This could also be down to the water level being too high in the fraxination chamber on the skimmer (unlikely in a hang on model)
If your pulling out a very dark sludgy mix then you know you have it right. You could possibly adjust the air/water mix to try and produce more skimmate if possible. This would result in a heavyer skim of the water. Beleave me you want to skim heavyly as you have no corals that would want to feed on the DOC (disolved organic compounds) in the water, so there presence can only be utilised in two ways.
1) adding to the biological load of your system, eventually becomeing denitrifyed into a nitrogen gas, with the final stage of denitrification being completed in an oxygen free bactereal colony somewhere in the system (usually the DSB, deep sand bed)
2) metabolised into algal tussiue which will eather be eaten and re-introduced back into the system. Removed by yourself and therefore effectivly exported. Or just held within the plant matter as it grows over the tank.
Basically if you keep your nutrient levels low then they wont get utilised by the micro algie because the biological load will be within capable peramiters to be dealt with by your nitrate reducing bactereal colonys. And therefore you should end up with a beutifull tank with many different macro (not micro) algies all competeing equally. Thats if they dont get munched first.
Overstocking pushes the limits of the denitrifying bacterea. This will mean that you will basically be running the system above acceptable levels of toxisity. Or you could even crash the system poisoning the bacterea and sterilizeing the entire system. The fish BTW will be long gone by this point, and you will notice that the tank smells too. In lower examples of this you can still have massive effects on the chemical parameters of the system, PH swings and such creating a very inhospitable but not inhabitable situation. This would only become evident in the fact that your fish live for only two years and never attain a good size. They still swim, sleep, eat etc, but not for long. Happy fish are a level above content fish, and a world away from fish that are just surviving. It helps bring out the finer points of charicter and natural behavour. But for those who have never seen it, would be unable to imagine how the fish could be "happy".
If you have anymore questions just ask. Ill stop writing now for fear of teaching you to suck eggs. But if theres anything above im sure someone will point you the right way.
Happy reefin.
Ok so maybe i was a bit hard on you earlier, and you obviously want this thing to work so i can tell you how i would do it, if you like.
Basically you have too many fish, there is no debate here, its a biological and physiological fact. This means either a bigger tank, with a skimmer to match. Or your going to have to trim back on your stock.
The fish you have chosen are probably the most unsuitable species to over-stock with only compounding eventual problems. This is primarily due to the eating habits of your fish. They are all incredibly messy, and produce a large ammount of waste while both eating and digesting.
Im betting the reason you have the two hermits is to over come this problem by having some sort of clean up crew. And beleave me with a tank like yours you will need it. Serpent stars will also help with this, and providing you have a suitable sand bed (3"-4" inches of Oolitic grade arragonite sand) a tiger tail cucumber or a queen conch would probably help a little too.
Just so you know your total fish length should be about 17 inches of fish. So, firstly get rid of the tang, as that requires a minimum of around 100 - 150 gallons due to swimming requirements.
Now bearing in mind that these calculations are for smaller community fish, and not the hulking beef cakes you have. I would stick with two of the big-uns. But admitadly they are small at present, but will grow very fast. So i guess you have a while before you have to start chosing your favorate two. I think the Volatan and one of the triggers would give a little variety in your inhabitants. Plus the lion wont swim half as much as any of the triggers leaving more swiming space.
You can wait till all your fish are arround 5 inches, then take out whichever trigger you dont want to keep, or get a bigger tank of course. But IMO the tang defenately has to go.
The skimmer is going to be very important to you because these guys are so messy. I really think that the little Back Pack is doing nothing. Beleave me there is skimmate sludge waiting in your system to come out, your skimmer just cant pull it. And this can be evident in the micro algal growth you may be expiriencing.
If you can set up a sump then all the better, but you may have overflow problems seen as the tank cant be drilled in-situ. Hang on skimmers arn't so bad, but you have messy fish so you need some power in that department.
With the back pack, id take an airstone and drop that in to add some bubbles, and remove the venturi. You can experiment allot with the setup so dont be afriad to try. The venturi's alone are very difficult to get a decent bubble size out of, which is why i wouldn't use a conventional venturi skimmer without some sort of needle wheel. HSA (High speed aspirated) skimmers are Venturi's but slightly better as induction is more effective creating a better air/water mix.
The Lime wood airstones are great at creating the correct bubble size, but need to be replaced periodically. You will know when because the bubbles will be much larger and the skimmate as you currently describe like dirty dish water. In addition to the limewood air stone you will need an air pump to run this. Go above the requirements presented by the airstone, allowing you to "throttle back" on the pump giving increased controll over the Air/Water mix. You will get much better at gaugeing this as the skimmte production increases.
The main principles are as follows:
Mix is too wet, I.E. like dishwasher liquid. Basically your using too much air. This is either pushing water directly into the collection cup, or foaming too rapidly taking too much water with the skimmate. So you end up with a mixture thats not thick and sludgy. This could also be down to the water level being too high in the fraxination chamber on the skimmer (unlikely in a hang on model)
If your pulling out a very dark sludgy mix then you know you have it right. You could possibly adjust the air/water mix to try and produce more skimmate if possible. This would result in a heavyer skim of the water. Beleave me you want to skim heavyly as you have no corals that would want to feed on the DOC (disolved organic compounds) in the water, so there presence can only be utilised in two ways.
1) adding to the biological load of your system, eventually becomeing denitrifyed into a nitrogen gas, with the final stage of denitrification being completed in an oxygen free bactereal colony somewhere in the system (usually the DSB, deep sand bed)
2) metabolised into algal tussiue which will eather be eaten and re-introduced back into the system. Removed by yourself and therefore effectivly exported. Or just held within the plant matter as it grows over the tank.
Basically if you keep your nutrient levels low then they wont get utilised by the micro algie because the biological load will be within capable peramiters to be dealt with by your nitrate reducing bactereal colonys. And therefore you should end up with a beutifull tank with many different macro (not micro) algies all competeing equally. Thats if they dont get munched first.
Overstocking pushes the limits of the denitrifying bacterea. This will mean that you will basically be running the system above acceptable levels of toxisity. Or you could even crash the system poisoning the bacterea and sterilizeing the entire system. The fish BTW will be long gone by this point, and you will notice that the tank smells too. In lower examples of this you can still have massive effects on the chemical parameters of the system, PH swings and such creating a very inhospitable but not inhabitable situation. This would only become evident in the fact that your fish live for only two years and never attain a good size. They still swim, sleep, eat etc, but not for long. Happy fish are a level above content fish, and a world away from fish that are just surviving. It helps bring out the finer points of charicter and natural behavour. But for those who have never seen it, would be unable to imagine how the fish could be "happy".
If you have anymore questions just ask. Ill stop writing now for fear of teaching you to suck eggs. But if theres anything above im sure someone will point you the right way.
Happy reefin.
Overstocked?
I think that would be a matter of opinion.
I can show you a 38 gallon high tank with a 15 gallon sump. Inhabitants are 1 healthy Yellow Tang, 1 Cinimmon Clown and one Beatiful Singapore Angel. The Singapore is the newest of the three and he has been in the tank for over two years.
I also have 4 blue legged hermits, 2 scarlet hermits and 2 emerald crabs, and a lone turbo snail.
There are only two things I think you need to consider. Get a sump and dump the hang on skimmer. Hang on skimmers suck.
Overflows aren't hard to make. I made one that is a modified version of Larry Willard' posted at http://saltaquarium.about.com/cs/diyoverflows/ but that is another story.
Ok, I will admit that I feel guilty about my Tang but he is very healthy. I tried to get Seaworld to put Shamu back in the Ocean and let my Tang have his tank. They don't think my Tang would draw much of a crowd. As soon as I get this house remodled ( this summer's project) he will be moving to a very large tank. I just haven't decided what to get yet.
I think that would be a matter of opinion.
I can show you a 38 gallon high tank with a 15 gallon sump. Inhabitants are 1 healthy Yellow Tang, 1 Cinimmon Clown and one Beatiful Singapore Angel. The Singapore is the newest of the three and he has been in the tank for over two years.
I also have 4 blue legged hermits, 2 scarlet hermits and 2 emerald crabs, and a lone turbo snail.
There are only two things I think you need to consider. Get a sump and dump the hang on skimmer. Hang on skimmers suck.
Overflows aren't hard to make. I made one that is a modified version of Larry Willard' posted at http://saltaquarium.about.com/cs/diyoverflows/ but that is another story.
Ok, I will admit that I feel guilty about my Tang but he is very healthy. I tried to get Seaworld to put Shamu back in the Ocean and let my Tang have his tank. They don't think my Tang would draw much of a crowd. As soon as I get this house remodled ( this summer's project) he will be moving to a very large tank. I just haven't decided what to get yet.
jethro wrote
I can show you a 38 gallon high tank with a 15 gallon sump. Inhabitants are 1 healthy Yellow Tang, 1 Cinimmon Clown and one Beatiful Singapore Angel. The Singapore is the newest of the three and he has been in the tank for over two years.
I would like to see that can you post that photo so I can judge for myself?
Hey thats jethro.....bodine......
The irony, the irony....
I can show you a 38 gallon high tank with a 15 gallon sump. Inhabitants are 1 healthy Yellow Tang, 1 Cinimmon Clown and one Beatiful Singapore Angel. The Singapore is the newest of the three and he has been in the tank for over two years.
I would like to see that can you post that photo so I can judge for myself?
Hey thats jethro.....bodine......
The irony, the irony....
Wooooooooo, Very nice Mouse, haven't seen you write essay like that for a while!
Very well said!
You've inquired if you should keep the SG up, what is the salinity you are maintaining right now?
Yes, micro bubble is the key but I don't think your skimmer is powerful enough to deal with the crap output in your tank. Moreover, The fluval canister can be very efficient of turning the raw food into nitrate, which is harder for skimmers to pull out of the water. Skimmers are better in pulling raw waste out of solution before it being broken down into NO2 and NO3.
My suggestion (if it is applicable for you interms of $$ and space) is to upgrade the skimmer to one that is better at handling large volume of water. The point is to allow it to skim out the junks before your canister picks it up.
The presence of airstone and airline in the skimmer chamber may itself disrupt the designed flow of water in the skimmer and may or maynot improve the performance of the skimmer. Plus the airstone will clog in no time.
Very well said!
You've inquired if you should keep the SG up, what is the salinity you are maintaining right now?
Yes, micro bubble is the key but I don't think your skimmer is powerful enough to deal with the crap output in your tank. Moreover, The fluval canister can be very efficient of turning the raw food into nitrate, which is harder for skimmers to pull out of the water. Skimmers are better in pulling raw waste out of solution before it being broken down into NO2 and NO3.
My suggestion (if it is applicable for you interms of $$ and space) is to upgrade the skimmer to one that is better at handling large volume of water. The point is to allow it to skim out the junks before your canister picks it up.
The presence of airstone and airline in the skimmer chamber may itself disrupt the designed flow of water in the skimmer and may or maynot improve the performance of the skimmer. Plus the airstone will clog in no time.
I just thought, ive got a canister filter on my reef. Why dont you do what i did and plumb the canister straight into the back pack. You will then have to T off the backpack so you can adjust the flow rate a little. And then drop in the airstone. That way you can also get rid of that time bomb Rio aswell as dealing with the air problem.
i've gone thru many skimmers over the years and here's my take.
If you tank has been setup and running for some time and no drastic bad algae growth stick to what you have.
The CPR you have is rated for 60 gallon. With a little more careful maintenance and careful feedings, that should be fine. Bigger powerhead doesn't necessarily mean more skimate. you will decrease dwell time in the skimmer.
A smaller skimmer may work all the time. A large skimmer may skim for a few hours and then be pulling nothing for days, a total waste of energy.
If you tank has been setup and running for some time and no drastic bad algae growth stick to what you have.
The CPR you have is rated for 60 gallon. With a little more careful maintenance and careful feedings, that should be fine. Bigger powerhead doesn't necessarily mean more skimate. you will decrease dwell time in the skimmer.
A smaller skimmer may work all the time. A large skimmer may skim for a few hours and then be pulling nothing for days, a total waste of energy.
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>Originally posted by Bodine:
<strong>Hey thats jethro.....bodine......
The irony, the irony....</strong><hr></blockquote>
Funny - I read Jethro and I just automatically thought it was you, Bodine. Not that you were using a different name, I just automatically made the switch. Got confused when you posted a quote from him...
<strong>Hey thats jethro.....bodine......
The irony, the irony....</strong><hr></blockquote>
Funny - I read Jethro and I just automatically thought it was you, Bodine. Not that you were using a different name, I just automatically made the switch. Got confused when you posted a quote from him...
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote
I want to know what to get.
My first skimmer, a Precision Marine HOT-1, is on it's way to my house.
It's got a small Rio pump driving it.
Should I change to a different brand or size? If so, what?
.... so.... smaller pumps are better generally?
I want to know what to get.
My first skimmer, a Precision Marine HOT-1, is on it's way to my house.
It's got a small Rio pump driving it.
Should I change to a different brand or size? If so, what?
greetings MandarinFish,
I'm a newbie to reefing myself. Just learning. I've tried to read Aquatic Systems Engineering by PR Escobal. Pretty tough math in there and i have to admit i just breezed over the calculation parts without getting out my calculator and really learning it.
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote
One thing that I actually did get though, and that is that the width of the skimmer is more beneficial than the heighth.
AHHH, i wish i'd learned that book now. Then i could give you a good answer. Heck, i just read up on which brand of skimmers most people said were best and saved up for a Euroreef for my 75g.
sorry,
po
I'm a newbie to reefing myself. Just learning. I've tried to read Aquatic Systems Engineering by PR Escobal. Pretty tough math in there and i have to admit i just breezed over the calculation parts without getting out my calculator and really learning it.
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote
Yes. 'well how small?'. I don't know exactly. Maybe someone else can give that answer. I hope.
One thing that I actually did get though, and that is that the width of the skimmer is more beneficial than the heighth.
AHHH, i wish i'd learned that book now. Then i could give you a good answer. Heck, i just read up on which brand of skimmers most people said were best and saved up for a Euroreef for my 75g.
sorry,
po
A lot of people told me to get a PM H.O.T.-1
so I did.
I can't do the math and am not interested enough in the specific equations. I'll take other peoples' word for it.
Euroreef seems arguably the best. For my little 55 gallon, I have a hard time justifying the cost, especially since I am mostly keeping fish and plants without corals.
Nice Onion reference, BTW pojohnny.
so I did.
I can't do the math and am not interested enough in the specific equations. I'll take other peoples' word for it.
Euroreef seems arguably the best. For my little 55 gallon, I have a hard time justifying the cost, especially since I am mostly keeping fish and plants without corals.
Nice Onion reference, BTW pojohnny.
Just thought I would throw in some comments about skimmer efficiency.
First off, the diameter of the skimmer is argueably not more important than the height. In many skimmers available today the increase in diameter is not matched with an increase in air injection, leaving the overall surface-to-bubble contact area lacking. Width does little for a skimmer except increase its ability to be "upgraded" if you will, in the future (provided more air is injected!). The height of the skimmer is definitly the most important aspect of the skimmer. It is the number one factor in defining the contact time the bubbles have with the water. Other skimmers such as the Centrifugal design of the SeaClone, and swirling action found in the Hot-1 and other skimmers help to increase contact time in a shorter skimmer.
The best skimmers have a very long contact time, very small bubbles size .5mm to 1mm, and a dense pack of bubbles in the main chamber so that it looks like white as milk.
First off, the diameter of the skimmer is argueably not more important than the height. In many skimmers available today the increase in diameter is not matched with an increase in air injection, leaving the overall surface-to-bubble contact area lacking. Width does little for a skimmer except increase its ability to be "upgraded" if you will, in the future (provided more air is injected!). The height of the skimmer is definitly the most important aspect of the skimmer. It is the number one factor in defining the contact time the bubbles have with the water. Other skimmers such as the Centrifugal design of the SeaClone, and swirling action found in the Hot-1 and other skimmers help to increase contact time in a shorter skimmer.
The best skimmers have a very long contact time, very small bubbles size .5mm to 1mm, and a dense pack of bubbles in the main chamber so that it looks like white as milk.
I spent some time looking a DIY skimmers. The real problem with defining a good skimmer is that nobody knows what they want a skimmer to do? Even the people designing them only have a rough description of what a skimmer does to a tank. If you study Escobal, you will find that residence time, diameter and air volumn all have effects on skimmer operation. Nothing in his book explains why the Hot-1 works at all. but users like it.
We don't know what effect a skimmer has on our tanks because nodody has done before and after testing. We can test what the skimmate has in it, but that doesn't answere what is left in the tank or even if the skimmer is a positive or negative effect.
We don't know what effect a skimmer has on our tanks because nodody has done before and after testing. We can test what the skimmate has in it, but that doesn't answere what is left in the tank or even if the skimmer is a positive or negative effect.
<blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr> First off, the diameter of the skimmer is argueably not more important than the height. In many skimmers available today the increase in diameter is not matched with an increase in air injection, leaving the overall surface-to-bubble contact area lacking. Width does little for a skimmer except increase its ability to be "upgraded" if you will, in the future (provided more air is injected!). The height of the skimmer is definitly the most important aspect of the skimmer. It is the number one factor in defining the contact time the bubbles have with the water. Other skimmers such as the Centrifugal design of the SeaClone, and swirling action found in the Hot-1 and other skimmers help to increase contact time in a shorter skimmer.
<hr></blockquote>
Good call MediaOne. I wrongly said diameter was more important.
I went back to the source. Here's an excerpt from the aforementioned book.
2nd Law: The bombardment rate, depends only on the duration of the tank water exchange and the diameter of the skimmer.
3rd Law: Increased skimmer length or height only raises the value of the absolute contact time but does not affect the bombardment rate.
5th Law:The air flowrate entering a skimmer should produce a full upward blossom of bubbles without excessive turbulence and is theoretically determined as a function of skimmer diameter, length, bombardment rate and absolute contact time.
6th Law: The value of bombardment rate within the skimmer, its length, diameter and airflow must all be properly chosen for optimum operation.
So if i understand it better now, then the bombardment rate (or number of times a clean air bubble hits a drop of water) is as important as contact time. However, I'm still unclear on the exact difference between 'contact time' and 'bombardment'.
Also, I was suprised by the books' advise that the tank turnover rate through the skimmer should only be twice a day. But i can imagine that as long as a skimmer had good scrubbing action with the proper blossom of air bubbles, the the water will get stripped good and proper.
,po
when i Woke
<hr></blockquote>
Good call MediaOne. I wrongly said diameter was more important.
I went back to the source. Here's an excerpt from the aforementioned book.
2nd Law: The bombardment rate, depends only on the duration of the tank water exchange and the diameter of the skimmer.
3rd Law: Increased skimmer length or height only raises the value of the absolute contact time but does not affect the bombardment rate.
5th Law:The air flowrate entering a skimmer should produce a full upward blossom of bubbles without excessive turbulence and is theoretically determined as a function of skimmer diameter, length, bombardment rate and absolute contact time.
6th Law: The value of bombardment rate within the skimmer, its length, diameter and airflow must all be properly chosen for optimum operation.
So if i understand it better now, then the bombardment rate (or number of times a clean air bubble hits a drop of water) is as important as contact time. However, I'm still unclear on the exact difference between 'contact time' and 'bombardment'.
Also, I was suprised by the books' advise that the tank turnover rate through the skimmer should only be twice a day. But i can imagine that as long as a skimmer had good scrubbing action with the proper blossom of air bubbles, the the water will get stripped good and proper.
,po
when i Woke
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