More questions...bioload/cycling this time!

[kwl718]

Sorry folks, I'm just full of questions! This is the first tank I've ever kept (it's for the four year old). I've been reading and reading, but can't always get the answers that way.

15 gallon, only fake plants. Finished fishless cycle last week, tank was clearing 2ppm of plain ammonia every day, in two doses, AM/PM so 1ppm every 12 hours.

I added two zebra danios on Monday afternoon (that's all the LFS would sell me for a new tank, cycled or not).

I've been testing every evening and so far, it's always been 0 ammonia, 0 nitrites and 0 nitrates...which is good for the fish, of course!

What I'm worried about is whether nearly all my hard earned bacteria bed is going to die off with just these two little fish and their tiny bit of food they eat or drop on the gravel.

Is this too little bioload to maintain much bacteria? I'm worried that, with no nitrates showing after three days, that there's practically no ammonia being produced and my bacteria will die.

Or, maybe I'm just paranoid and it takes a while to see the nitrates?

I think I became too emotionally attached to that bacteria during the five weeks of fishless cycling and I miss seeing evidence of their activity .

Thanks!

 

[echoofformless]

The amount of bacteria is relative to the amount of ammonia and nitrite.

As long as your cycle is complete and there are both types of bacteria present, even the tiniest little fish will keep the tank cycled.

The trick when adding more fish is to do so a little a time so that more bacteria can grow to meet the new bioload demand. In an established biofilter, these creatures will multiply within hours.

Sounds like you're doing fine to me.

 

[Hound]

Essentially speaking yes your bacteria will die back enough so that there are just enough of them to keep the ammonia from two small fish processed. At this point you are probably going to have to build up the aquarium slowly. In the case of your LFS it seems a little knowledge is a bad thing. Application of that knowledge in this case was poor. As just pointed out though you can generally double the bio load every 24 hours or so. Myself I tend to wait up to two weeks between stocking.