[Neil D]

If I were to seed a 40g tank with filter media, decor and gravel, how long would the bacteria take to multiply?

(40g tank, 3 goldfish, a Marineland 350 filter, airstone)

It's been one night since I put the fish in and ammonia is ~.20 ppm.

 

[Mo]

The amount of nitrifying bacteria mainly depends on one thing, other than the amount of oxygen, light, etc. mostly food. As in ammonia. The amount of nitrosifyers can very greatly depending on the amount of food, in this case ammonia present. Nitrosifyers, such as nitrosococcus, And nitrosomonas. (there are more types of nitrosifyers but these are the only in an FW system) will convert toxic substances such as ammonia into equally toxic ones, in this particular situation, it would be nitrites, nitrites then get converted into less harmful substances by nitrifying bacteria. By nItrobacter (there are more types of nitrosifyers but these are the only in an FW system) the result of this would be nitrates. So the amount of nitrates you have can represent the amount of ammonia being produced if you don't have any plants in there or any other way to remove nitrates. You would want to achieve media from an over stocked tank or from a very established fully stocked tank. And take about 1/3 or the media. It should cycle in a small amount of time. Around 1-2 weeks

 

[Neil D]

Okay thanks. Just wondering. The tank where I got the media from is from my divided betta 10g tank. It is cycled, but obviously not overstocked.

 

[registereduser]

I "seeded" my 20 gallon with gunk from my cycled 5 gallon and it took about a month. The water was cloudy for about 2 weeks, bacteria bloom, I guess. It was a fish-in cycle and the 3 I had in the 20 showed no signs of stress.

 

[Neil D]

Ok thanks for the input. Yeah they seem okay too, just eking around the bottom and stuff. They seem to like to stay together, but that's probably because they're new.