Ammonia And Nitrite

[New Boy]

I set up a new tank two weeks ago and just let it run with no fish until Saturday. On Saturday I added 3 mollies and on Sunday I took a sponge out of my sisters tank (that has been running with fish in so should have some bacteria on) and put it into my tank......I haven't seen nitrite or ammonia go up at all - is this because I used part of someones filter media to kick start my filter or is it just too soon as the mollies only went in Saturday?

The mollies look fine so just wondering if it's safe to add some more fish at the weekend.

Cheers
Andy

 

[sussexgirl]

I set up a new tank two weeks ago and just let it run with no fish until Saturday. On Saturday I added 3 mollies and on Sunday I took a sponge out of my sisters tank (that has been running with fish in so should have some bacteria on) and put it into my tank......I haven't seen nitrite or ammonia go up at all - is this because I used part of someones filter media to kick start my filter or is it just too soon as the mollies only went in Saturday?

The mollies look fine so just wondering if it's safe to add some more fish at the weekend.

Cheers
Andy

I set up my tank and added a sponge from my other tank in just the same way you have. It still took a week before I had any amonia reading and another week before I got a nitrite reading. Tank cycled in 3 weeks total though so it was a lot quicker than starting from scratch.

 

[New Boy]

Thanks

By adding some filter media from someone else's filter how much will that speed up my cycle? As the fish produce ammonia and there is already some bacteria there does that mean that I won't see an ammonia spike but will see a nitrite spike (as the bacteria that feeds on nitrite will have died off without any nitrite to feed on)?

Just wondering how it works...

Cheers
Andy

 

[Inchworm]

Hi New Boy

You have just done what is called "cloning a tank." In other words, by adding an established source of beneficial bacteria you have basically bypassed the cycling process.

Now, this is not to say that you will see any rise other than nitrates; that will depend on the amount of bacteria you added. If it is enough to support the fish in the tank, all will remain normal. If not, you should expect a mini-cycle where the ammonia and/or nitrites go up until the bacteria have time to reproduce themselves enough to consume it.

If you have more than enough bacteria they will die off since they don't have enough food. Then, when you add more fish, they will reproduce again until they reach the proper numbers.

That's why it's always better to add fish just a few at a time.