Thanks.
Guess I'm on the right track because that's what I have been doing. I've read that this is common in new tanks. Some things I've read say you go from brown algae to green algae in new tanks. Is this true ? My tank has been running for about 4 months now. I really don't want to use chemicals to treat it. I use only ro/di water for pwc and top offs. Feed every other day.