Can you have to much Filtration?????

[Duncan]

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

[carlejo]

I heard this before from koi keeping colleague that ives quite close to me.

What sort of size filters would we be talking, in your opinion, would be too big for a pond.

We could use mine as an example. 4200 g....... 130 ltrs aerated K1 in first bio, second bio is is exactly same as first, third bio is j mat cartridge 26" deep x 30" wide........and TT of 10 kg of BHM off skimmer(pumping approx 2000gph)
8 tosai in pond since last July, and growing fast.

What would be too much filtration ?
cheers
Carl

[Geoff9]

I enjoyed that Duncan
You have just told me why my K1 in the nexus is still very light opposed to someone with a lot more koi per 100 gallon,I have 180ltrs of K1 and 25 ltrs of Bio chips and I've been thinking perhaps I have far to much,I think I could take 80ltrs out and still have plenty,but to be on the safe side I will take 5ltrs out per week and see how it goes.

Regards Geoff

[carlejo]

Geoff, mine hasn't changed colour in 4 years........ still just an off white colour, whereas my mate Dave, his is very brown.......

[tomy2ponds]

Hi I would have said yes a filter can be too big you can only colonize the filter by the amount of food available for the filter bacteria to survive.So if a filter was say 100% bigger than what was needed apart from when feeding heavily in the summer and even then a good percentage would not be colonized so for this reason I would say yes a filter can be too big.Weather or not the bacteria would colonize all of the front of the filter leaving the last chambers devoid of bacteria I would not know(If it was a multi chamber filter)I would have thought it would grow where the best food supply is.

[eds]

I would add to this that the type of media will play a big role in this too. In freshwater planted tanks the trend is for larger and larger filters to ensure there is enough flow in the tank (10 times the tank's volume per hour is the recomended turnover) and this means people have huge external filters, or even two of them. They then fill these with sintered glass media with huge capacity and then, because the'r filter is do big with a huge amount of media and doesn't block quickly, they neglect their water changes and cleaning and then all of a sudden algae breaks out with the build up of organic wastes and tiny ammonia spikes. I stick with more reserved filters and add a circulation pump like a koralia to increase the current to even more than 10x and it works much better IMHO.

I would have thought though Duncan, in the hypothesis you stated that you would still get a bigger build up of bacteria in the first chambers of the filter where the ammonia laden water is entering as the bacteria will be competing for the nutrients and if you're 'upstream' of your neighbour then you're ahead of the game surely? It would be the latter stages of the filter that would have less bacteria wouldn't it? Unless of course your turnover was so fast to negate that effect?

[Gazza]

Hi Guys,

I think we have all heard or said this before but sometimes in my case has been when someone is is upgrading or asking about a filter for a pond where the manufactures say it does XXX when in fact it would be lucky to do XX so when they look at the next available unit they just think its way to big 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"

I think filtration is very overlooked as some people just think they can throw a load of media in which means they can pump it faster and this then means they can have loads of fish that will grow massive overnight....not true

No mater what system you have you have to allow the water to pass through the media at the correct speed to do its work otherwise you will not get the full potential from the media and the filtration will not function as it should do.

Geoff,

i would not worry to much about the colour or your K1 i have seen this a lot and IMO the reason some peoples K1 look darker than others is a few things PP & dirt many dealers will have very dark K1 but will also be carrying out quarantining of new fish and parasite treatments and this will include PP (some also use it for maintenance) so it will always be darking due to the staining. Also if the K1 is not cleaned out as often as perhaps yours then again it will go darker due to the waste which is sticking to the media and in doing so making it darker all you need to make sure is that your system keeps the water with good with low ammonia and nitrite

[boogatee]

Great post Dunc .... but if I follow your logic, too low a stocking level will have the same impact .... correct??

It really is a balancing act between feeding rates and capability of the filter.

[Duncan]

Hi Guys

Great post Dunc .... but if I follow your logic, too low a stocking level will have the same impact .... correct??

It really is a balancing act between feeding rates and capability of the filter.

Chris thats exaclty right mate the two scenarios are the same

carle this is just theory based on scientific data and my knowledge i have no idea waht the exact figures would be for media surface area V stocking levels but if i were a betting man i would say it would be closer to your system if at all given you have an extreme set of filters

lets look at BHM just for one example a three tier shower with what i would describe as costly as it is a measly amount if filter media in will keep a large system woith a good level of stocking, any one who's been to see mikes set up at Yume will bare this out his two smaller ponds have an enormous amount of stock for very little media by comparison this would appear to support my theory but all this is just guess work based on sound data

so im also guessing that BHM is buiudling huge amounts of layers on each individual rock and as you work through the layers the activity get less and less for ammonia and nitrite conversion till finally you get to the dormant stage of the matrix then finally the inner core where denitrification is taking place

so it would appear in this instance the system of the bio-film or matrix works and less is more maybe thats the secret of BHM in that its the perfect habitat for this matrix forming to take place and the matrix forms better here on this media than any other type? im just think outloud here i dont know but itsa possible this is the locked secret of BHM

if you compare that to K1 which i think is a pretty poor media myself its just to shiny and smooth to get anything to lock to i would treat this with some kind of acid before use i would wnatg it as pitted as possible .
but maybe K1 is the exact opposite of BHM when it comes to creating the perfect bio-film ?

BTW i use static K1 in an eazy and i find it perfect for just this purpose but little else and mine in two years has never changed colour i think this is because it has pretty much an impervious surface that nothing can adhere to and that maybe includes bacteria as it does seem to take a hell of a long time to mature

i do hope youe enjoying this section and the stuff we are getting into aint it great to flex that muscle in your head ???

[Gazza]

Is it me guys or is Duncan coming round to BHM there will be a shower on his pond soon

Yes this is a great thread and thought provoking Duncan and even though i have been up to my neck in "stuff" this section has got me thinking on lots of things its great mate

[B.Scott]

Scaling it all down a bit this is a situation you often see in people setting up a Q-tank for new koi. I have often seen people with a running Q-tank with a small fish or two in it to keep the filter running. Others will have a Q-tank running with nothing at all and expect the bacteria to magically appear on the media. In one case it is over filtration and the other it is nothing more than passing water around. Both situations come down to a scenario were you move from a nutrient deficit to an enormous surplus once any substantial amount fish are added to the system. Mind you I do feel that a system that has in the past held a mature layer of bio-film will bounce back in a greatly accelerated period of time compared to virgin media. I feel as long as the bio-film matrix is there, active or not, the recolonization does get a jump start. My own view of a bio-film is akin to plack on teeth. Once it gets ahold you can try to kill off the bacteria within with mouthwash or toothpaste, but it will back double quick if you don't visit the dentist and have the plack scrapped off. It's basically social housing for bacteria and nature hates a void. At the end of the day there is little use in having more filter than you are feeding unless it is anticipation of a greater future filter load. Creating something out of nothing just isn't going to happen.

B.Scott

[Geoff9]

Hi All
Just took a picture of my Nexus as I cleaned it out been running for 5.5 years the water is always spot on with regards to Parameters,I only ever used PP to clean the K1 when it first went in the Nexus.

Regards Geoff

[boogatee]

I have a nexus running my immensely overstocked setup and my parameters and growth rates are satisfactory (and better than most) ... however I don't think the point is about which media is better than which, but more about ensuring that your (generic your) setup is operating at its optimum - be it a shower or a black box. I know that mid summer I can feed the nexus a 15kgs sack of food in 2 months - that's 3-4Kgs per 1000 gals per month and it wont skip a beat. I also have no blanket weed and never have had any. I use BHM, but it's submerged in a filter used on my skimmer line. Again, some may argue not the best use of BHM.

What I can tell you though is that my K1 media does change colour between winter - when I pretty much stop feeding and summer when I feed the heaviest. I've also never had any side effects after using treatments be it PP or Telmin (which I swear by) ... so whilst plastic media may not be the best (???) and sponges may be the most labour intensive ... most media can be made to work very well, it all depends on how much time and effort you are prepared to put into nurturing the setup.

[Brek]

I heard this before from koi keeping colleague that ives quite close to me.

What sort of size filters would we be talking, in your opinion, would be too big for a pond.

We could use mine as an example. 4200 g....... 130 ltrs aerated K1 in first bio, second bio is is exactly same as first, third bio is j mat cartridge 26" deep x 30" wide........and TT of 10 kg of BHM off skimmer(pumping approx 2000gph)
8 tosai in pond since last July, and growing fast.

What would be too much filtration ?
cheers
Carl

well put it this way, I have 12 fish between 25 to 45 cm in 1500 galls, and 30l of K1, not aerated since the summer when it all got kick started with the heat never had a nitrite reading over .01mg/l only gone to 0.05 as I have been chucking in the odd handful of food in for them and temps been sat around 8 deg cel until mid feb, now at 12 deg cel.

[Duncan]

Hi All
Just took a picture of my Nexus as I cleaned it out been running for 5.5 years the water is always spot on with regards to Parameters,I only ever used PP to clean the K1 when it first went in the Nexus.

Regards Geoff

Geoff

the reason for PP'in K1 is to burn the surface at at start up the surface of this stuff is so shiny the bacteria can't grip it easily thats not saying they dont just thats its harder than most other media's

so i tihink it was recommended to soak it in a high concentration of PP to burn and rough the surface up give bacteria and better surface to grip

dunc