Quote Originally Posted by gronlaura
Tank is almost done cycling and I am preparing for my first big water change (I have 35 gal RO water on hand).

This morning - .25 ppm ammonia, 0 nitrites, 10 nitrates, pH 7.4, GH 4, KH 5. I check my water parameters daily.
I'm confused. Looking at those numbers, I would say that your tank hasn't even begun cycling yet. The first step is build up of ammonia, which you have. Second step is conversion of ammonia to nitrite with the ammonia eventually remaining at zero and nitrite building up. The final step is the conversion of nitrite to nitrate with the nitrite eventually remaining at zero and nitrate building up. The fact that you have ammonia is odd, especially if your nitrate going into the tank is zero after using RO water. I'm wondering if maybe the ammonia test kit is old or if you're simply slightly color blind (not meant to be an offensive remark; myself as well as many others here have difficulty reading those color charts, especially when it comes to that 0 and 0.25 ammonia).