What is causing my tank to go brown, i.e. growth on everything

a picture would really help. What i would do is just turn on 1 light and keep it on for 8 hours and see what happens. Make sure you wait about 2-3 weeks for improvement because it takes time to see improvement. Also a single T5 should be fine for a low light tank.

one more question do you have T5NO or T5 HO?
 
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