Aquarium is completely green

You also can start changing water on a weekly basis for awhile, if not more frequently. Use a siphon to vacuum the gravel, helps alot. If you are very lightly stocked (what kinds of fish do you have, btw?) you can, in time, go back to less frequent wtaer changes.

Definatly lessen your tank-light-on time!
 
I had a similar problem in my 110 community tank. The problem turned out not to be lighting or over feeding, but the type of food. the food was rich in spiruella, (I think thats how it is spelled) and when feed, even sparringly, my tank would "scum" up. I've tried adding snails and shrimp and all sorts of algea eaters, and to no avail. I stopped using that brand food..... all better. Take it for what its worth. Hope this helps even a bit.
 
Like Jericho said, you don't need to move the fish for a blackout. The UV sterilizer will kill off any free floating organism that passes through it's light but won't touch stuff that is anchored down, like the algae attached to the tubing. If the algae on the tubing is hard to remove then a blackout will kill it, though you'll still need to scrub off the dead matter.
 
what kinds of fish do you have, btw?

I have a gourami, iridescent shark and a red-finned shark. All are pretty small. I'm already vacuuming the gravel with a siphon to no avail. I'm gonna work with the advice on here and use a UV sterilizer in combination with blackout periods.
 
If you have no live plants...You do not have to keep lights on at all. Just turn on when you want ot see fish, turn off when leaving.
 
I faced a similar problem with my 20 gallon. It never got completely green but I was constantly scrubbing algae off. I got a live plant from Petsmart and it had some snail hitch hikers. Saw a huge difference with just 4 of them so I went to the lake and got a whole bunch more. No more algae problem.
 
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