bio-bateria discussion

[pingapple]

I have a 10 gallon tank with a simple overhead filter box on it, keeping 1 angelfish. The tank has been running for a year.

There are two layers of filter wool in the filter box. If I replace one layer of them with new one, will there be enough bio-bacteria to do good nitrification? Any experience in doing that? Do you think any difference for replacing the top layer or the bottom layer?

Some local fish shops use 1 or 2 simple filter boxes to keep lots of fish in a 5 gallong tank.

I have the following guess. Not sure whether they are correct.
(1) A small surface area is enough for a lot of nitrification bacteria to grow on it.
(2) Bacteria can survive with very small amount of ammonia and nitrite.
(3) Bacteria can nitritfy a huge amount of toxic comparing to the little quantity which can keep them barely surive. (Analogue: bateria can survive with one mouth of rice but it can eat 10 bowls of rice without problem)
(4) For a sessioned tank, taking away half of the bacteria in a tank, the other half can still do the nitrification with double the time duration. That will still be a very short time for a tank with normal load and a simple filter box.

[sungod666]

Whether a small area can accomodate lots of bacteria depend on the quality of the filter media.
beneficial bacteria break down ammonia and nitrates

For your tank, wither get a small japanese external filter or the Tetra silver and black canister. put some biohomme plus and problem solve. if no place for external cannister, i suggest the eheim powerball internal filter. i have a 35L tank ard 10 gallon too, i use the powerball and keep yamamto and frontosa and i change the water only once a month. iin addition to the powerball, i have a small diy tupperware filled with biohomme. water parameters are excellent and bioload no sweat with the powerball.