B) I have been keeping my aquarium light on from 8:00 p.m. until 6:00 a.m. Should I have the light on during the daylight hours instead? I have some brown algae on the back of my tank and was wondering if the combination of daylight and aquarium light was causing it. My tank is not in direct sunlight at any time of the day. I was also thinking about planting my aquarium and was wondering whether the light should be on during the day or night for the plants - or if it even makes a difference.

All things, plants and fish, need a period of darkness as well as a period of light to properly grow and thrive. It is perfectly plausible that you can turn your night into day and vice-versa if you wish, but you do need to make sure that there are sufficiant hours of DARK as well as light. Your fish will sit on the bottom of the tank in their favorite spots very quietly and "sleep" every day (night) and need this time to regenerate. It is not good to turn lights on and off during this time. They need the uninterrupted sleep time.

Plants, too, will respire at night - giving off CO2 in the dark and O2 in the day. They need this time, also.

If you light the "night" just make sure you give them at least 8 hours of "night" when it is dark - close blackout drapes, or cover the tanks if necessary! Fish will thrive if the dark and light periods are consistant. They do not have a clock to tell if it is 3pm or 3 am.

Thanks - I like seeing the tank lit at night. I will set the timer to turn the light on at 11:00 a.m. and off at 11:00 p.m. There may be a little light from the room in the morning when I get ready for work - but on days I am off there will be complete darkness for eight hours. Glad I asked!