Cycling Question - High Nitrite Levels

Barlow · Jan 14, 2010

Hi all.

I've been reading the many posts on this site about cycling tanks and although I've learned a lot I'm still rather confused. However, hopefully someone with more fish-keeping experience may be able to help.

Just over 2 weeks ago I set up a new 90 litre tank, and added the filter media from my old one (but no fish yet). For the first week I didn't have any test kits so was unable to take any readings. Since then I've managed to buy two Tetra kits and have tested the Ammonia and Nitrite levels. The Ammonia is very low and has been like that for a week now, but the Nitrite reading is off the scale (I can't remember the exact numbers) and has stayed like this.

Is that ok (and should I just be patient)? Or do I need to take some action (such as adding Ammonia) to bring the Nitrite levels down?

Any help or advice that you can give would be really appreciated.

Thanks
Jon

VaegaVic · Jan 14, 2010

You should ideally be adding something as a food source for the bacteria anyway.
You've used old media, with established colonies but..what are they going to eat with no fish in there?

Try and do a part-fish less cycle.
The Nitrites will come down on their own in time, but you need to keep adding ammonia to keep the cycle on tick-over.

waterdrop · Jan 14, 2010

Agree with VV. You always want to "qualify" the operation of the biofilter in situations like this. The readings are telling you that the biofilter is not fully re-prepared for handling fish yet.

Its good that you starting picking up test kits. TetraTec make good kits and I'm assuming you have their liquid ones. You'll also need a pH test kit and eventually a nitrate(NO3) test kit. But the ammonia and nitrite(NO2) kits are the first needed so you've done the order right.

Your next big challange is actually finding the right type of household cleaning ammonia. Its a "generic" type product usually found in mop and broom sections of stores. Its obviously not a big money maker so it can be hard to find. The stuff you need is plain clear ammonia that's free of dyes, fragrances, surfactants or soaps. If you can see it and shake it, it should create bubbles for 2 or 3 seconds just like water. It should not foam or that would suggest surfactants or soaps in it.

The members get a kick out of hearing how your seach for the right stuff goes. Its good to look around the store even if a clerk tells you its not there. The opposite is also good, to ask a clerk even if you don't see it out on shelves. In the UK the members can help with specific places like Boots and others. In the USA, Ace or TrueValue Hardwares usually carry it.

~~waterdrop~~