Media For Bio-filter

[BillyBobThai]

I am in the planning stage to build a test setup to grow catfish in a high intensity

2 cubic meter tank with a 2 cubic meter bio-filter and a pond, 2 meter by 4 meter by 1/3 meter deep filled with these local water plants from the canal.

The water will flow from the fish tank to a setteling tank before entering the pond. The water will be pumped to a bio-filter tower and gravity back to the fishtank. A complete water change will be made once every hour.

My question is, what to use for my media in the bio-filter? The media needs to be inexpensive as quite a bit will be needed. I have considered gound up charcol, gravel, plastic mosquito netting, plastic shade cloth, shreded plastic bottles from the recycler, and coconut husk, but they disolve in a little over a week.

Once I have made this setup to work, I plan on setting up enough tanks so that I can turn over 1 tank a month. This will take place at my home so the midnight

shoppers should not be a problem.

Any thoughts will be apperiated.

Thanks

[wackysleet]

I am in the planning stage to build a test setup to grow catfish in a high intensity

2 cubic meter tank with a 2 cubic meter bio-filter and a pond, 2 meter by 4 meter by 1/3 meter deep filled with these local water plants from the canal.

The water will flow from the fish tank to a setteling tank before entering the pond. The water will be pumped to a bio-filter tower and gravity back to the fishtank. A complete water change will be made once every hour.

My question is, what to use for my media in the bio-filter? The media needs to be inexpensive as quite a bit will be needed. I have considered gound up charcol, gravel, plastic mosquito netting, plastic shade cloth, shreded plastic bottles from the recycler, and coconut husk, but they disolve in a little over a week.

Once I have made this setup to work, I plan on setting up enough tanks so that I can turn over 1 tank a month. This will take place at my home so the midnight

shoppers should not be a problem.

Any thoughts will be apperiated.

Thanks

As bio filter in my koi pond I use pumice stone the size of walnuts placed in nylon net bags about the size of an arm chair cushion and underneath that in the same size cushion nets I have the spikey black plastic balls found in any aquarium shop, my filter is 4ft x4ft x4ft and there are 3 of these, the cost of materials {medium} was in the region of a 1,000 baht, my wife made the cushion cover containers out of nylon net.

[Maizefarmer]

I use plastic coke bottles and milk crates - packed into a 2mdeep x 2mwide x 3mlong concreate tank cast into the ground.

No - I don't farm catfish - I have a pond in the garden with Koi.

The tank is divided into 3 x 80cm long sub-tanks:

Water path through the filter as follows:

Extracted from sump at the centre/deepest part of the Koi pond with a pump.

1) Pumped into the bottom of sub-tank 1 - rises up slowly through 2m's of bio-filter media (made of plastic milk crates and plastic coke bottles cut in half). After rising through the filter media to the top of the tank it overflows into a plastic gutter, which has a 4" diameter pipe attached to it.

This pipe drops down to the bottom of tank 2.

2) The water nows enters into tank 2 at the bottom - rises up slowly through 2m's of bio-filter media (more plastic milk crates and plastic coke bottles cut in half). After rising through the filter media to the top of the tank it overflows into a plastic gutter, which has a 4" diameter pipe attached to it.

This pipe drops down to the bottom of tank 3.

3) The water nows enters into tank 3 at the bottom - rises up slowly through 2m's of bio-filter media (more plastic milk crates and plastic coke bottles cut in half). After rising through the filter media to the top of the tank it overflows into a rockery feature located at the far end of the koi pond - the water flowing down the rockery feature re-air-reates it before flowing back into the pond.

What keeps the water flowing from one tank to the next? - construct the tanks so each succesive one is slightly lower than the next.

What controls the rate at which the water flows from one tank to the next? - the rate at which it is pumped into t1 - gravity now takes over

The key to these filters is: surface area - provided by the plastic milk crateas and milk bottles for algea/bacteria to grow on.

Only problem with these filter - they take a long time to establish and mature (30 - 45 days) , but can collapse in a matter of days.

They are in every sense of the word "balanced systems" - change one characteristic, and the whole system needs to re-adjust to survive. But when working properly, they work well.

There is a relationship between bio-filter surface area, water volume, flow rate through filter, fish load and temp - do some reading up (I can't remember what it is) - anyway, plastic bottles and plastic milk crates work fine. Don't use coloured plastics at/near the surface of the filter - sunlight will break them down.

[c64]

I am in the planning stage to build a test setup to grow catfish in a high intensity

2 cubic meter tank with a 2 cubic meter bio-filter and a pond, 2 meter by 4 meter by 1/3 meter deep filled with these local water plants from the canal.

The water will flow from the fish tank to a setteling tank before entering the pond. The water will be pumped to a bio-filter tower and gravity back to the fishtank. A complete water change will be made once every hour.

My question is, what to use for my media in the bio-filter? The media needs to be inexpensive as quite a bit will be needed. I have considered gound up charcol, gravel, plastic mosquito netting, plastic shade cloth, shreded plastic bottles from the recycler, and coconut husk, but they disolve in a little over a week.

Once I have made this setup to work, I plan on setting up enough tanks so that I can turn over 1 tank a month. This will take place at my home so the midnight

shoppers should not be a problem.

Any thoughts will be apperiated.

Thanks

Mods: I'm not putting an ad up for another site...

It's a danish guy somewhere on another thai site (send a pm and I'll provide a link without violating the regulations here), who has a high intensity fish breeding programme. Worth a look. I was reading it under the farming links there. He has actually managed to get a work permit for doing farming/fishery operations due to research on reuse of the water in the operation. 90% water reuse and producing about 2-3 tonnes of fishes for sale per week.

If you read, he will give valuable hints of how to manage your micro filters, water towers, oxygen levels in the water, plumbing system and so on.

Regards

-C64-

Edited July 11, 2009 by c64