Can you have to much Filtration?????
Posted: Sat Feb 26, 2011 1:12 pm
Hi
Something Geoff said made me think, this was “you can’t have enough aeration”
This reminded me of another similar saying “you can’t have enough filtration” and this got me thinking “well actually can you have too much filtration?”
Of course I have heard these saying many times before usually branded about by folks who have little or limited knowledge but can pass themselves off as knowing a bit with this simple saying knowing full well it can do no harm and at worse will create a safe state for a pond to be in albeit over kill but an expensive way of going about things. But actually can there ever be a satiation where too much filtration can work against you in some or all circumstances? And this is where this little missal is heading
In a previous thread we have already discovered there can be a situation where by you can in effect have to much air in pond. Not that this will result in anything more detrimental than the size of the dent it creates in your wallet. The reason for this is water at any given temperature water can only saturate with O2 to a certain point and no more this is because oxygen as a very low affinity when dissolved into water where as something like CO or CO2 is able to saturate much higher but the way O2 works is as follows :
At low temperatures water will saturate with O2 higher than at higher temperatures so for example let say the water is at 5 Celsius this would roughly be the maximum saturation of O2 a round 12mg/l or 12 PPM ( parts per million) or simply put the maximum amount of Oxygen the water is capable of carrying.
Now take the same volume of water but heat to 26 c the water now would only hold or saturate to around 6 mg/l or PPM and would be the point in the temperature range where for a garden pond it would hold or saturate to the least amount of Oxygen .
While nothing really can raise these saturation points there are other factors capable of driving these saturation point lower still for any given temperature one is barometric pressure other include other solutes and obviously this relates to high TDS and of course contaminates
The reason for this maximum saturation point is complex but basically and the reason it cannot be exceeded in normal condition is because of the partial pressure principle, two factors directly influence the rate of transfer from air to water and this is partial pressure difference at saturation.
What this means in layman’s terms is the concentration of any gas in water at saturation point when being subject to further interface with atmosphere if the water is under saturated ( in deficit ) it will take on more gas . if the water is supersaturated ( in surplus) it will release gas out of solution and there for will not take on anymore gas no matter how much air gas you subject it to so the saturation of O2 in water for any given temperature is totally dependant on surplus or deficit . In answer to something that was said earlier if deep water in a pond was under saturated down deep is where the exchange would take place and nnot at the surface as the bubble breach, however, the suggested saturation stratification of water in a koi pond does not exist. In reality a koi pond is not deep enough and has a high circulation rate so oxygen and indeed the so called “heat stratification” does not exist in reality .
Ok this bought me to my next though is it possible to have to much filtration ion a general sense I would have to say no but I could envisage a point where to much would not help you
Let’s explain my thinking on this.
All filters work or more appropriately function by supply and demand in other words you supply x amount of nutrients and you will grow bacterial that this given amount of nutrients can support. If you increase the nutrient input you will increase the colony size of bacteria simile if you take the nutrients away the colony will decline in proportion to the supply , in this case we are talking about nitrogen and of course chemotrophic bacteria.
To simplify this imagine a garden of grass with 20 ft x 20 ft with a 12 rabbits in residence and all are happy this is because there is enough food to support that colony size the colony wont shrink because there is enough resource neither will it increase because although there is enough resource for the current colony it wont support any more
Now lest assume we expand the fence to 40x 40 we would see the colony of rabbits increase accordingly to maybe 20 rabbits and then stabilise at that. But if we pulled the fence in to 5 x 5 we would see not only the extra rabbit die off but some more of the original 12 to maybe 6 this is a scientific term called competitive exclusion and in fact this principle can be used to exclude technically to exclude pathogens by starving them out but that’s another story
A filter behaves in exactly the same way, it will only colonise to the amount of nitrogen being produced and of course this amount is as a result of your stocking level and feeding rate. put simply more fish = more feed = more nitrogen = more bacteria
Less fish = less feed = less nitrogen= less bacteria. Simple enough to understand by anyone more is more less is less , so if you go along for x amount of years with 20 fish and suddenly increase this stocking level by another 10 fish you would expect to see a temporary rise in pollutants ammonia, nitrite etc: as you don’t have the colony present to support the extra fish. As this is a logical solid train of thought, in the case of filter bacteria would this indeed be the case? The short answer is probably yes but it’s not as simple as I have just described.
Filter chemotrophs do not behave in the same ways as most other bacteria filter bacteria form a matrix what’s called a bio-film in other words they settle on a media one on top of each other locking each other together with leg like joints, these layers will continue to form like layers of an onion. If you peel one layer away a fresh layer is underneath these bacteria.
The top layers is obviously the most active the layer under that will also be active but to a much lesser degree the layer under that will maybe also contributing to converting nitrogen and as you descend through the layers this activity will become less and less till you get to the lower layers which will be in stasis. so as these bacteria becomes exposed they start to r become fully active and take the place of the top layer this may take a few hours but they will pick up the slack and so on and so on as you remove layers in the bio-film this phenomena can be of benefit to us as koi keepers which I will shortly get to
So in a filter that’s just adequately sized you can expect this phenomena to take place, layer upon layer of bacteria forming.
Now suppose the filter is way over sized what do you think will happen?
The bacteria will tend not to form these complex matrix/films because they can spread out , I hypothesize based on reason that in an over sized filter bacteria because they have a constant but limited food supply wont multiply to the extent they form a complex matrix or a much reduced matrix what they will do is spread out across the whole media available with so much space on the media they tend not to form complete or complex matrix/bio-films or much reduced bio-film
At the end of the day to the average hobbyist keeping an average stocking density in the correct volume of water with the correctly sized filter, the way “this” guy keeps his fish will differ very little the same hobbyist with the same givens but a larger than usually filter they will both keep fish with their water parameters in line. This fact is supported or born out personally for me buy the fact that as I visit lots of pond in an advisory capacity even the poorest ponds you can imagine ponds with the lowliest filtration systems you can dream up i.e very small filters still manage to keep parameters like ammonia and nitrite under control, they merely struggle with nitrate which is understandable because the average filter is not geared to busting the nitrate molecule but generally there is very little difference in day to day nitrogen management in all there types of systems believe it or not.
I can here you all saying so what’s the point well for me the So what is if you apply a caustic treatment like Potassium permanganate to your pond what do you think is going to happen?
You will burn the bacteria off on your media this is a fact you cant get away from it you will destroy a layer of bacteria if you add another dose you will burn another layer off and this will continue till there are n o more layers left. Now you can see where I’m going and what I was pondering, lest talk in extremes if an over sized filter has lets say for arguments sake one layer, and a compact filter has several multi layers if you burn the top layer away with a treatment such as C/T, PP or formaldehyde what is the likely outcome of future parameters in the pond I think even an undersized filter would fair better under these conditions as this would have multi facets to its matrix
Couple to this lets say you suddenly increase your stocking level by 50% which system would pull up the slack faster the one with multi layers or the one with limited or single layers ?
This is my hypothesis based on my knowledge and an enquiring mind it makes logical sense based on what I know of bio-films and how bacteria perform in a filter and scientific theory on such things as competitive exclusion , gas exchange etc :
All I’m asking you to do as a reader and fellow hobbyist is always challenge convention question what has never been questioned and we will uncover more and move forward.
Hope you enjoyed my missal and it has sparked something off ion you to start questioning what we just accept from day to day, this is the way many of the enervation you are now using have come about if these people/enervators just went with the flow we would still be look at a hole in the ground and wondering why the fish keep dying
Something Geoff said made me think, this was “you can’t have enough aeration”
This reminded me of another similar saying “you can’t have enough filtration” and this got me thinking “well actually can you have too much filtration?”
Of course I have heard these saying many times before usually branded about by folks who have little or limited knowledge but can pass themselves off as knowing a bit with this simple saying knowing full well it can do no harm and at worse will create a safe state for a pond to be in albeit over kill but an expensive way of going about things. But actually can there ever be a satiation where too much filtration can work against you in some or all circumstances? And this is where this little missal is heading
In a previous thread we have already discovered there can be a situation where by you can in effect have to much air in pond. Not that this will result in anything more detrimental than the size of the dent it creates in your wallet. The reason for this is water at any given temperature water can only saturate with O2 to a certain point and no more this is because oxygen as a very low affinity when dissolved into water where as something like CO or CO2 is able to saturate much higher but the way O2 works is as follows :
At low temperatures water will saturate with O2 higher than at higher temperatures so for example let say the water is at 5 Celsius this would roughly be the maximum saturation of O2 a round 12mg/l or 12 PPM ( parts per million) or simply put the maximum amount of Oxygen the water is capable of carrying.
Now take the same volume of water but heat to 26 c the water now would only hold or saturate to around 6 mg/l or PPM and would be the point in the temperature range where for a garden pond it would hold or saturate to the least amount of Oxygen .
While nothing really can raise these saturation points there are other factors capable of driving these saturation point lower still for any given temperature one is barometric pressure other include other solutes and obviously this relates to high TDS and of course contaminates
The reason for this maximum saturation point is complex but basically and the reason it cannot be exceeded in normal condition is because of the partial pressure principle, two factors directly influence the rate of transfer from air to water and this is partial pressure difference at saturation.
What this means in layman’s terms is the concentration of any gas in water at saturation point when being subject to further interface with atmosphere if the water is under saturated ( in deficit ) it will take on more gas . if the water is supersaturated ( in surplus) it will release gas out of solution and there for will not take on anymore gas no matter how much air gas you subject it to so the saturation of O2 in water for any given temperature is totally dependant on surplus or deficit . In answer to something that was said earlier if deep water in a pond was under saturated down deep is where the exchange would take place and nnot at the surface as the bubble breach, however, the suggested saturation stratification of water in a koi pond does not exist. In reality a koi pond is not deep enough and has a high circulation rate so oxygen and indeed the so called “heat stratification” does not exist in reality .
Ok this bought me to my next though is it possible to have to much filtration ion a general sense I would have to say no but I could envisage a point where to much would not help you
Let’s explain my thinking on this.
All filters work or more appropriately function by supply and demand in other words you supply x amount of nutrients and you will grow bacterial that this given amount of nutrients can support. If you increase the nutrient input you will increase the colony size of bacteria simile if you take the nutrients away the colony will decline in proportion to the supply , in this case we are talking about nitrogen and of course chemotrophic bacteria.
To simplify this imagine a garden of grass with 20 ft x 20 ft with a 12 rabbits in residence and all are happy this is because there is enough food to support that colony size the colony wont shrink because there is enough resource neither will it increase because although there is enough resource for the current colony it wont support any more
Now lest assume we expand the fence to 40x 40 we would see the colony of rabbits increase accordingly to maybe 20 rabbits and then stabilise at that. But if we pulled the fence in to 5 x 5 we would see not only the extra rabbit die off but some more of the original 12 to maybe 6 this is a scientific term called competitive exclusion and in fact this principle can be used to exclude technically to exclude pathogens by starving them out but that’s another story
A filter behaves in exactly the same way, it will only colonise to the amount of nitrogen being produced and of course this amount is as a result of your stocking level and feeding rate. put simply more fish = more feed = more nitrogen = more bacteria
Less fish = less feed = less nitrogen= less bacteria. Simple enough to understand by anyone more is more less is less , so if you go along for x amount of years with 20 fish and suddenly increase this stocking level by another 10 fish you would expect to see a temporary rise in pollutants ammonia, nitrite etc: as you don’t have the colony present to support the extra fish. As this is a logical solid train of thought, in the case of filter bacteria would this indeed be the case? The short answer is probably yes but it’s not as simple as I have just described.
Filter chemotrophs do not behave in the same ways as most other bacteria filter bacteria form a matrix what’s called a bio-film in other words they settle on a media one on top of each other locking each other together with leg like joints, these layers will continue to form like layers of an onion. If you peel one layer away a fresh layer is underneath these bacteria.
The top layers is obviously the most active the layer under that will also be active but to a much lesser degree the layer under that will maybe also contributing to converting nitrogen and as you descend through the layers this activity will become less and less till you get to the lower layers which will be in stasis. so as these bacteria becomes exposed they start to r become fully active and take the place of the top layer this may take a few hours but they will pick up the slack and so on and so on as you remove layers in the bio-film this phenomena can be of benefit to us as koi keepers which I will shortly get to
So in a filter that’s just adequately sized you can expect this phenomena to take place, layer upon layer of bacteria forming.
Now suppose the filter is way over sized what do you think will happen?
The bacteria will tend not to form these complex matrix/films because they can spread out , I hypothesize based on reason that in an over sized filter bacteria because they have a constant but limited food supply wont multiply to the extent they form a complex matrix or a much reduced matrix what they will do is spread out across the whole media available with so much space on the media they tend not to form complete or complex matrix/bio-films or much reduced bio-film
At the end of the day to the average hobbyist keeping an average stocking density in the correct volume of water with the correctly sized filter, the way “this” guy keeps his fish will differ very little the same hobbyist with the same givens but a larger than usually filter they will both keep fish with their water parameters in line. This fact is supported or born out personally for me buy the fact that as I visit lots of pond in an advisory capacity even the poorest ponds you can imagine ponds with the lowliest filtration systems you can dream up i.e very small filters still manage to keep parameters like ammonia and nitrite under control, they merely struggle with nitrate which is understandable because the average filter is not geared to busting the nitrate molecule but generally there is very little difference in day to day nitrogen management in all there types of systems believe it or not.
I can here you all saying so what’s the point well for me the So what is if you apply a caustic treatment like Potassium permanganate to your pond what do you think is going to happen?
You will burn the bacteria off on your media this is a fact you cant get away from it you will destroy a layer of bacteria if you add another dose you will burn another layer off and this will continue till there are n o more layers left. Now you can see where I’m going and what I was pondering, lest talk in extremes if an over sized filter has lets say for arguments sake one layer, and a compact filter has several multi layers if you burn the top layer away with a treatment such as C/T, PP or formaldehyde what is the likely outcome of future parameters in the pond I think even an undersized filter would fair better under these conditions as this would have multi facets to its matrix
Couple to this lets say you suddenly increase your stocking level by 50% which system would pull up the slack faster the one with multi layers or the one with limited or single layers ?
This is my hypothesis based on my knowledge and an enquiring mind it makes logical sense based on what I know of bio-films and how bacteria perform in a filter and scientific theory on such things as competitive exclusion , gas exchange etc :
All I’m asking you to do as a reader and fellow hobbyist is always challenge convention question what has never been questioned and we will uncover more and move forward.
Hope you enjoyed my missal and it has sparked something off ion you to start questioning what we just accept from day to day, this is the way many of the enervation you are now using have come about if these people/enervators just went with the flow we would still be look at a hole in the ground and wondering why the fish keep dying
but as we know many filters do not do what they say on the tin and normally best to go a bit bigger hence "you cant have enough filtration" 
