My tank had just gotten over a brown diatom outbreak when I decided to change the substrate. I put some of the old gravel in a stocking in my filter to help with the BB since I cleaned the tank and filters pretty good when I changed the substrate ... had forgotten I didn't want to do that because I feared the diatoms would come back. I don't know if that little bit of gravel caused it or changing the substrate caused it .. all I know is it's back.
Unfortunately I can't put either snails or Oto's in my tank (it's stocked with Bluegills). What I have to do is take 1or 2 plants (stem plants) out a day and put it in my 29gal tank that has pond snails and 3-Oto's and the next day it's sparkling clean (doesn't take overnight, just easier for me). It doesn't take very long when I put the plant in there for the Oto's to find it and starting chowing down. I'm sure it's the Oto's that clean it that quick and not the pond snails because if I look several hours later it appears a lot cleaner and it might only have 1 or 2 snails on it. The next day there are more snails on it .. just something else for the Bluegills to eat when the plant goes back in the big tank. The only good thing is it gives the Oto's something to eat since there isn't any algae in my 29gal .. hey got to look for an upside anyway I can. LOL
I sure wish I could figure out a way to put the Oto's in my big tank without the fish eating them so they could clean up the stuff I don't want to have to take out .. . like my Sword plant and driftwood. If I could figure out how to confine or shield them in a small area at a time that would help. Of course it's kind of a moot point now that the weather has cooled off. Don't think the Oto's could handle the cold water temp in the unheated bluegill tank.
I know this was a long and round about way of saying that Oto's seem VERY effective at cleaning brown diatoms.
