Hi, I have two questions about drop checkers. 1. I added a drop checker to my 5 gallon (cleaned it first), and two days later there was this growth on it. http://imgur.com/AiWgv I cleaned it again, and two days later the same growth came back. So I removed it, cleaned it, and added it to my 20 gallon. The growth came back. Anyone know what this is, or how to avoid it? 2. The bottle of drop checker solution that came with my drop checker is very small, and is hard to read when it's in the checker. Should I water this down before I add it to make it sort of transparent? Aquarium water, or tap water? Thanks!