Bright Green Algae

[ryanrichter]

For the past week or two, I have been getting this bright green algae (on the glass only), after the metal halides have been on for the day. The algae is pretty much isolated to the top of the tank. Any suggestions?

[RobertG]

I would say check to see what Phospahte levels are. Do you use an RO/DI? How old are your bulbs? Without an RO/DI you probably have high phos. thats were I noticed my prob. My bulbs being old had some funky growth going also. Hope it helps.

Robert