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Hello

I have been cycling my tank for about 1 week and 3 days. The first week I used flake food to get the cycle going. That week I was away on holidays. I tested the ammonia before I left. It was 1ppm. When I got back it was 0, same with the nitrites. The nitrates were 10ppm (up from zero). To test that the tank was cycled I added some ammonia I got. Unfortunatly I added way to much (up to about 20ppm+ I think). I did a 60% water change. That barly effected the ammonia readings. So I did another water change of 90%. It brought the readings down to 4ppm.

Now to the important part. Its been 2 days after that happend. The ammonia has gone down to 2ppm and the nitrites havent gone up past 0ppm. The nitrates are at about 1ppm though. What the heck is happening?

Shaun

When you fishless cycle a tank, you have to have a controlled dose of constant ammonia to feed the nitrifying bacteria. When you went away for a week after you put the fish food in, the bacteria most likely died off due to lack of food, that's why you got a zero zero reading when you came home.

The ammonia you put in when you got home was, as you said, way too much. Did you gravel vac when you did your 90% water change? Water changes in themselves are bad for cycles, and even worse are gravel vacs. You're not seeing any nitrites yet because it's been too short of a time. It takes almost a week for them to show if done properly.

I would just empty it out, clean it up and start fresh. Use the ammonia you have (what kind is it, anyway?) to spike the tank to 5ppm. Keep this going daily until you see nitrites. Then, back the dosing off by half until your nitrItes spike. Keep dosing half until your nitrItes drop and the nitrates rise. Once this happens, you're good to go. It doesn't take much less time than when adding fish to cycle, but it's much safter and quicker by a week or so.