Dry Rock and long-term bacterial bloom

[TimT]

Originally Posted by Gobytron

I would definitely be exploring other explanations other than bacterial bloom.

An easy way to be sure it's bacteria is to check your nitrates. No or minimal nitrates means it's bacteria and not a buffer issue.

Originally Posted by jon.smolders

Maybe this is the simplest option? Would it matter what size I used? I was leaning toward a 9W Green Killing Machine because I can get one shipped for about $75...

The hazy water and whitish growth on the inside of the glass is indeed bacteria. Free floating bacteria are very easy to kill with a UV, so the 9 watt should be adequate. Just make sure to put nothing larger than 300 gph pump on it or you won't get a high enough dosage to kill the bacteria.

Originally Posted by Jaws

Not me. I'd be surprised if there wasn't enough oxygen though. My tank has a coast to coast overflow plus 3 Maxspect Gyres, 2 MP40 Vortechs and 4 Tunze 6105s so there's plenty of surface agitation too. Or does that not matter in this case?

Current within the tank is good for promoting gas exchange at the surface but a skimmer is much better. Put the UV on your tank and it should clear the bacteria very quickly.