how long to keep light on?

i have 2x24 t5 ho for my 20g tall. i currently have a hammer, frogspawn and a few zoas in there, how long should i keep the light on for? i have been leaving it on for about 10 - 12 hours a day, is that too long? Thanks.

 

If your not having alot of algea growth from the lights being on for a while , then no thats not to long.

 

i turn my lights on when i get up and turn them off when i got to sleep. all in all thats about 16 hours but ive been told thats to long because ill have algae probs. which are starting to form. but the lfs said actual daytime so from the time the sun rises till it sets during the summer months and dothat all the time so id say your ok unless you have very needy corals but i dont all it does is create algae and raise your electric bill.

 

8-10 hours a day is the ideal amount of hours, you will in fact start to get algae problems if you run it for 14+ hours a day nevermind just the electricity bill
hope that helps

 

yea, startin to see some cyano on my LR and a cover of neon green algae, not sure what they are, they're just neon green, no hair or anything, as if the rock was painted that color.

 

no matter how long you have them on for you will have a algae bloom as you are putting more lights on your aquarium. this will balance out in a month or two. it is only the algae in the sand and on the glass so nothing horrid like bubble. or hair.