I've been cycling a second tank and monitoring it daily. On Saturday the parameters were pH 6.6, ammonia 1.0, nitrite 2.0, nitrate 10.0 I do almost daily 50% water changes because the Nitrite gets so high, but this is what shocked me. On Monday the parameters were pH 6.6, ammonia 2.0, nitrite 5.0, and...something I've never ever seen before nitrate was 160.0, the maximum on the chart totally blood red. I dose Prime every day and usually the maximum dosage. Do snails cause nitrate because the only odd thing about my tank is that I have literally an infestation of pond snails. I can probably count more than 50 on the glass alone. p.s. I did double check the nitrate test because I thought it was surely a mistake, but the same result. I did a 80-90% water change and the nitrate went down to 5. The next day it was at 80 so I did another water change and it went down to 10. Two days later it went up to 40 and that's where I am now.