I have my lights on for about 12 hours a day, strictly for my viewing pleasure, lol. I have algae growth, but every morning I wake up to a clean aquarium. Reason- my turbo's. They are primarily nocturnal and go crazy while I sleep. My ratio is as I stated earlier 1:2gallons. They may not be required, but they surely make a difference IMO. Rock Blennies are really big algae eaters to, and are one of the more docile blennies.