Green hair/string algae taking over tank! Help!
I've been battling this stuff for a few months now and nothing I've tried works. It covers the driftwood like an ugly moss carpet, entangles my filter, smothers the leaves...
I have a 55 gallon tank with 4 goldfish. Plain gravel substrate and tons of plants. The lights are 64 watts T8 and on 8 hours per day. No ferts, CO2 or any of that stuff. I've tried manually removing the stuff but it attaches very strongly to the glass, filter, rocks, gravel, and worst of all the plant leaves. Usually I can't pull it off of the leaves without damaging the leaves.
So I guess these are my options:
-reduce the light even more (take out a bulb, leave it on less time) but I'm worried that'll damage the plants
-add CO2 (but I don't want to mess around with CO2 and goldfish, plus it's expensive)
-add excel (I'm worried that adding enough excel to kill the algae will also kill my vals and possibly harm the goldfish)
-algae eater fish (but the little ones are too tropical for my tank and plecos grow too large)
-nerite snails (sounds good, but would the goldfish eat them?)
-add duckweed (I've heard it helps to reduce the excess nutrients and blocks out light, but the goldfish would probably eat it)
-algaecide (but I'm worried it will hurt the fish/plants)
So... I'm stuck. Any suggestions?