I have a 20 gallon tank for 3 weeks now. I put two live rocks in it within a few day to start a cycle without fish. For the last two weeks, all my levels were zero, so I thought it had already cycled and I added two clown fish last Saturday night. The water was looking cloudy yesterday, and so I did a 20% water change. This morning I tested my levels and my Ammonia was at .50 and Nitrite and Nitrates at 0. I called the local fish store and they said don't let it get higher, but don't keep changing the water because this is the real deal cycle. So this evening I tested and Ammonia was at 1.0. I did a 10% change, and it was still at 1.0. I don't even want to go to sleep because I am afraid it will rise a lot over night. Any advice??? Sleepless in Virginia.