im not an expert,but i think it happens to newly set up tanks.happened to me,drove me crazy i tried every thing then did the unthinkable...got a plecostomus...gasp,before everyone goes nuts on here and tells you not to get one,just find one that doesnt grow to a monster and your problem is solved.
Looks like brown algae/diatoms. I'm having a heck of a time with it in my tank right now. It is not harmful to fish, which is really the only good thing about it. I just scrub it off the glass really good during each PWC. With my tank, there is always some of it present.
ive had many time in my betta bowls and i just thought maybe it has to do with the light being so bright ?? it dont think it is harmful, it never affected my fish, it is like the easiest type of algae to clean, maybe get an algea eater they only get 3-4 inches at most???
If it's diatoms (brown algae) and it looks from the picture that's what it is, then it will go away by itself after a while. It's not harmful. It feeds off silicates so once the silicates are exhaused it will go away.
Mine didn't go away as others suggested it might. So I bought three Ottos. 48 hours later, my brown-infested tank was perfectly clean. Would only suggest one for a 5G tank though assuming there is room for one.
__________________ Sharon : Melbourne, Australia
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