Biofilters are not needed!

[JohnHuff]

This post is actually for Waterbug, who has said it a few times. I didn't believe it either at first but I've come to the conclusion that biofilters are not necessary for pretty much any pond that has plants in it.

My realization only came after I started my indoor aquariums. A lot of the simple filters sold (such as the HOBs that come with the tanks as a starter kit or sponge filters) don't even include real media for bacteria yet for decades aquarists have been keeping their water toxin free. And that is because beneficial bacteria grow on every surface in the tank and there is already immense surface area on the glass and on the gravel.

The same thing with ponds. The filters that established companies such Tetra or Laguna sell for up to a few thousand gallons hold a ridiculously small amount of media compared to the surface area of objects inside the pond. The amount of media that they hold really is laughable.

I had built my own filters for both my tanks and pond including Bakki-type filters, Skippies and filters of my own design. These filters contained massive amounts of surface area (using K2, bioballs or gravel) compared to the store bought filters and even then I realized that they probably didn't amount to that much more compared to the natural surfaces inside the pond. For example, if you look at the amount of surface area that Skippies contain in their media compared to the amount of natural surface area in a pond that the Skippy matched to, you will see that the pond will contain a much larger surface area for the bacteria to colonize. All that is really need is water flow to bring nutrients to that those surfaces.

So what kind of filtration does one really need for a watergarden or a pond with plants? You only really need a pump to circulate the water and a mechanical filter to filter out solids. The ponds natural surfaces and plants will take care of the rest.

At one time, I had 4 biofilters running in my pond. This year I've dismantled 3 of them (except for the one that originally came with the pond and is part of the pumping system) and I can say that the water parameters are just as good as when I had 4 biofilters. And my pond is slightly overstocked too.

So to anyone who is thinking or worrying biofilters, I say don't worry about it. If you have a waterfall, just create a wet-dry biofilter under the waterfall by added gravel and small rocks to the bottom of it and add some plants, and that'll be all the biofiltration you'll ever need.

 

[Mmathis]

What about fish load? If your pond was overstocked, would the "natural" surfaces be able to keep up?

As soon as I get my bog built, the Rubbermaid/Skippy is going to be repurposed [QT]. My thought was to have a TT for extra filtration & oxygenation [and to eventually add a PP/FF]. Not an over stocked pond, but will probably be at it's limit. TT necessary or not?

 

[JohnHuff]

What about fish load? If your pond was overstocked, would the "natural" surfaces be able to keep up?

As soon as I get my bog built, the Rubbermaid/Skippy is going to be repurposed [QT]. My thought was to have a TT for extra filtration & oxygenation [and to eventually add a PP/FF]. Not an over stocked pond, but will probably be at it's limit. TT necessary or not?

What I'm saying is that any added biofiltration surface area would be insignificant compared to a pond's natural surface area.

With my 800g pond, if I had added a Laguna/Tetra store bought filter, the additional surface area of the media included would add maybe 1-2% extra surface area.

With my homemade filters at the max. (3 tower filters with gravel plus 1 Bakki-type shower with K2 media) I figured I added maybe 20% surface area.

With the recommended sized Skippy, I think it adds maybe 5% surface area to the pond.

On the internet, there's a chart somewhere showing the surface area of each type of media so you can calculate roughly the additional surface area you're adding. So I don't know, how much will 5% or 20% help with overstocking? Only testing the water will tell.

 

[koiguy1969]

fish load is only one factor.... feeding is bigger. 1 lb of food makes the same amount of wastes weather 5 or 15 fish eat it... filters also remove wastes from the water column. so the debris dont remain decomposing. producing ammoniums. a lightly stocked pond, and lightly fed fish .. no doubt you can get by with no filtration. ... you think i could keep the fishload i keep in my basement pond without filtration? not a chance....800 gals with 6 20" fish and maybe up to 100, 2"- 5" juveniles. dedicated koi ponds...not much chance you could get by without filtration.

 

[capewind]

fish load is only one factor.... feeding is bigger. 1 lb of food makes the same amount of wastes weather 5 or 15 fish eat it... filters also remove wastes from the water column. so the debris dont remain decomposing. producing ammoniums. a lightly stocked pond, and lightly fed fish .. no doubt you can get by with no filtration. ... you think i could keep the fishload i keep in my basement pond without filtration? not a chance....800 gals with 6 20" fish and maybe up to 100, 2"- 5" juveniles. dedicated koi ponds...not much chance you could get by without filtration.

I think you misread the original post .. he aknowledge a solids filter;-)

 

[JohnHuff]

filters also remove wastes from the water column. so the debris dont remain decomposing. producing ammoniums.

Ya, that's why I said biofiltration. I have 4 pre-filters attached to my pump, those are my mechanical filtration.

Also, I should qualify natural pond, not a basement pond or a one of those completely bare ponds without anything in it except 4 walls and a base. I'll edit to add that to my OP, oops too late. But I do mean to say natural pond as I did in an earlier post and also what Waterbug had alluded to.

koiguy: don't take my word for it. You can calculate your pond surface area and calculate the additional surface area your media will give you.

 

[crsublette]

If your primary goal is to maintain a watergarden with a properly stocked, likely more on the low end, with little feeding, then additional mechanized bio-filteration is unnecessary.

You are absolutely correct that the terribly inefficient typical store bought, static submerged media, biofilters are not any better, that is actually worse, than a typical watergarden with plants. Those pressurized, all-in-one, combo filters are about the worst pond store products out there consumers would buy for their pond. When avid hobbiests say "steer clear of pond store products", they are talking in particular about this stuff. The only pond store filters that might be a tad better are the filters that utilize the wet/dry construction.

Surface area is not the point. It is all about how the surface area is utilized, that is static submerged media such as that plants provide versus a very highly oxygenated, agitated media in fluidized filter or high flow wet/dry shower filter. For example, compare the results of taking X amount of surface area in a static submerged media and then compare this to taking the same X amount of surface area in a fluidized or high flow wet/dry shower filter. I would gaurantee the results would not be even remotely close to each other.

A true testament of what you are proposing is already in pracice in the aquaponic arena where they truely do rely on their garden to maintain the biological filtration except they must use tremendously more surface area to accomplish what is achieved versus the better hobbyiest crafted filters. They even go as far as to construct their systems to emulate the very highly oxygenated, wet/dry contruction of a bio-filter due to the obvious additional benefits for nitrification and benefits to the plants.

Also, look at the amazon planted aquariums. They utilize only plants and these tanks sustain very few fish, while at the same time the vast majority of the tank are plants. This is fine for them since the primary focus is not on the fish and this is how it is for watergardeners.

Watergardeners primary focus is not on fish. All of the watergardens I have seen have a very nice compromise between an average or below average fish stock density and plants. The watergardens I have seen are no where near to be considered "overstocked". Actually, watergarden ponds are more properly stocked the way a pond for beginners should be stocked with fish, but not everyone are into doing the "plant thing", that includes the extra maintainenance involved in regards to trimming and removing the plant decay, etc. However, it is undeniable that plant decay will contribute to problems if it is not properly managed; otherwise, we would not care about scooping dead algae out of the water.

 

[dieselplower]

If your primary goal is to maintain a watergarden with a properly stocked, likely more on the low end, with little feeding, then additional mechanized bio-filteration is unnecessary.

You are absolutely correct that the terribly inefficient typical store bought, static submerged media, biofilters are not any better, that is actually worse, than a typical watergarden with plants. Those pressurized, all-in-one, combo filters are about the worst pond store products out there consumers would buy for their pond. When avid hobbiests say "steer clear of pond store products", they are talking in particular about this stuff. The only pond store filters that might be a tad better are the filters that utilize the wet/dry construction.

Surface area is not the point. It is all about how the surface area is utilized, that is static submerged media such as that plants provide versus a very highly oxygenated, agitated media in fluidized filter or high flow wet/dry shower filter. For example, compare the results of taking X amount of surface area in a static submerged media and then compare this to taking the same X amount of surface area in a fluidized or high flow wet/dry shower filter. I would gaurantee the results would not be even remotely close to each other.

A true testament of what you are proposing is already in pracice in the aquaponic arena where they truely do rely on their garden to maintain the biological filtration except they must use tremendously more surface area to accomplish what is achieved versus the better hobbyiest crafted filters. They even go as far as to construct their systems to emulate the very highly oxygenated, wet/dry contruction of a bio-filter due to the obvious additional benefits for nitrification and benefits to the plants.

Also, look at the amazon planted aquariums. They utilize only plants and these tanks sustain very few fish, while at the same time the vast majority of the tank are plants. This is fine for them since the primary focus is not on the fish and this is how it is for watergardeners.

Watergardeners primary focus is not on fish. All of the watergardens I have seen have a very nice compromise between an average or below average fish stock density and plants. The watergardens I have seen are no where near to be considered "overstocked". Actually, watergarden ponds are more properly stocked the way a pond for beginners should be stocked with fish, but not everyone are into doing the "plant thing", that includes the extra maintainenance involved in regards to trimming and removing the plant decay, etc. However, it is undeniable that plant decay will contribute to problems if it is not properly managed; otherwise, we would not care about scooping dead algae out of the water.

I tend to agree with this post more than the original post. The water flow of a well designed biofilter helps to aerate the water, bring more water into contact with the bb's, can include UV from the Sun, etc etc. Stationary bb on the liner etc are good but can't do everything.

 

[sissy]

heat of the summer is what could be a problem .I know when the heat of summer hits here it can be hot and dry for a week or 2 and my pond is in direct sun .I have my pumps now sitting in buckets with lava rock in them .I had success with this way last summer except they were in a tote .The buckets have holes drilled in them all around

 

[HTH]

Water garden vs natural pond makes a huge diff. To a degree' I agree. But I stand by what I said in the other thread.

Also heavier feeding generates more ammonia not just more solid waster.

The real thing here is goal. If you goal is min work and you don't care if you are maybe stunting your fish due to feeding less then they need to grow yeah it works. The bigger the pond the better it works. My ~15'x45' lily pond was unfiltered, just aireation, you could not see the water for the lily pads and the fish loved it. No health problems and by the end I was feeding a 20 or 25lb bag of koi food during the hot months last year. But the water was seldom clear, with mechanical filtration it might have been as there was only green water in the spring.

 

[sissy]

I have only ever fed my fish 3 or 4 times a week and it sure did not stunt there growth ,at least not aggie and bert in 9 years now they are over 2 feet long and growing .I wish I could stunt there growth .No aerator no UV and no skimmer so know clue why my pond works .2 filters with lava rock and plants

 

[HTH]

So obviously between the natural food in the pond and what you feed them it was enough for them to grow.

People confuse what we want with what the fish want. Mostly UV and skimmers are for people. We want nice clean ponds so we can see the fish. The fish would be just as happy or happier with a mud bottom. Air would be nice.

 

[sissy]

I guess since it has been 9 years and not one lost fish and fairly clear water I stick with what works for me .I can't say it will work for every one .I saw the pond where the guy raises the koi and was amazed I could see nothing . They just use nets they drop and pull in to catch the fish .I guess they eat a lot of tadpoles since I have so many frogs .

 

[DrCase]

I have a small pot i grow lotus in i dont remember the gal i would think 30
I put some koi eggs in last year and had some small fry
They grew well in there and over winterd in the same pot
They move real fast i know there are atleast 10 koi in the tub 3" long

Waterbug has a point

 

[JohnHuff]

Ya, we can all agree on a few things, a watergarden such as mine doesn't really a biofilter, a naked overstocked tank will probably not have enough surface area/bacteria to detox it and those store bought biofilters are absolutely crap!

Still, beneficial bacteria is known to be highly efficient and as Waterbug used to say most of the air exchange is done on the water surface, so is surface area more important or is a very highly oxygenated agitated media more important? My brother in law is a bigger believer in this than me, he has a fish tank that does not have a biofilter at all. He relies on a single airstone and some algae on the walls to biofiltrate his overstocked tank. I keep waiting for his fish to die but so far apparently the water flow and air from the airstone is circulating the water enough for the bacteria to take care of his ammonia and nitrites.

And incidentally, I do have DIY moving bed filters in both my indoor tanks and if I needed to get rid of a lot of ammonia, that would be my choice too - it's small and compact and highly efficient.

The only way to really know if highly oxygenated agitated media vs static surface is more important is to lab test it. But all I really wanted to say is that watergardens don't need biofilters and will agree that naked overstocked ponds will need them.