So in my tank I have only a 15 watt fluorescent 10,000K light over my 20H. However, I have my lights on for maybe about 15 hours a day; I put them on at 7am when I go to school and turn them off maybe around 10pm. All I have are fish and a piece of live rock. Would it be fine for me to have it be on from maybe 7:00am-10:00am and then turn off from about 10:00am-3:00pm and then turn on from 3:00pm-10:00pm. This means I would runthe lights for a few hours, then turn them off for 5 hours, and then run them again for 7 hours. I heard that this is a good way to get rid of algae as they can't withstand the changing light too well. What do you guys say. BTW, the algae I see it just green algae on my glass, only a small bit, and some on my deco. Also, will coraline algae eventually start to appear on its own or do I not have even close to enough lighting to get coraline growing. I have a piece of live rock with some coraline on it that came already on it.