In the past few weeks, I have been noticing that brown algae is becoming a problem in more than one of my tanks. First is started off in my 10 gallon - growing on the decorations and such. Now it has to be scrubbed off on a twice weekly basis to look decent. My 2.5 betta/cory tank also has this problem, as does my 6 gallon. Mostly this algae is growing on the decorations, with a little bit on the glass. It is almost rust colored in the 10 gallon, but more brownish in the other tanks.

What should I do? I realize more/less light won't make a difference. I have tried doing more frequent water changes (twice a week, both times cleaning gravel, though once more thoroughly) and feeding less, but it just seems to be getting worse. My nitrate levels are normal for me, they're a bit high (not unsafe) but my tap water has nitrates in it so I can't do much about that.

After doing a bit of research, I heard that adding "Phos-zorb" might help. I don't have a phosphate test kit, but it seems that phosphates are important for this type of algae's growth. Also, would adding ottos help significantly? I don't want to add ottos to all my tanks though, there isn't room! What else can I do? It's unsightly and getting frustrating. Obviously, I don't want to add chemicals unless I have to, but I don't know what to do. Any opinions and ideas welcome, thanks!

Brown algae is not really algae, it is caused by diatoms. Most algae eating fish will eat it - so if you have space for an Otto. Of course, you could always add the Otto until it is clean then move him to the next tank...

Brown algae is almost always indicative of low light.

try this

http://www.algone.com/

my 125 looked HORRID! But two week after i added this ,it looks perfect again.

Another fix is flying foxes..they love the stuff.

Have you tried replacing the bulbs?

If it is indicative of low light, would increasing the lighting in the tank work? The thing that doesn't make sense as far as that though, is that one of the tanks with the problem is the 6 gallon, which has several live plants in it and has 10-12 hour lighting. I can increase the lighting in the 10 gallon though, as it only has the lights on for viewing and feeding.

What exactly would you recommend LL? I am thinking I will perhaps get an otto or two, do you think that is the best idea?

Also brown algae is normal in the new tank, just after the cycle period is finished, it might also just disapear by itself.

Thanks silly, I had read that also, but these tanks aren't new at all.