ok, that's funny, i made a post, it said wait min, but then it wasn't here?
6 hours i think, they come on before I get home and go off after I go to bed (most nights i don't get in till after 9 or 11). Lights go off around 3am or so I think. no algea, and happy fish. (don't have any corals either, which may require more/less light?)