Algae Help

From your description it sounds like diatoms (soft, easily rubbed off).
Generally diatoms are found in two circumstances. New, immature tanks will give rise to them until they mature. If the tank is mature it can be seen in where there is less than adequate circulation and in some cases lower than adequate lighting can result in an outbreak. Your lighting definitely needs changing at this point. You can probably find a 'daylight' bulb that will fit your fixture at Home Depot or Lowe's and it should cost less than buying at the LFS.

If it's diatoms, Otocinclas cats will do a nice job on it for you. They are tiny, but industrious algae eaters and like to have company so get a couple at least.

Len

I am experiencing this exact same problem! I also have a 10G tank with the stock 15W bulb. My tank has only been set up and running for about 2 months, so I assume that's why I'm getting the brown algae. It flared up for a few days pretty bad, but I did a couple of water changes and cleaned the glass and it seems to be under control for now.

I would like to get a few otos for my tank, but I was wondering what would be a good number? Are these a schooling fish? I currently have 4 zebra danios and ideally I'd like to get only 2 otos since its a small tank. That way maybe I'd still have room for another small school of tetras or something similar. Thanks.