I have about 40 x week old dwarf gourami fry in a 20L tank with a sponge filter. There is some java moss and floating weed in there, bare bottom. The sides of the tank are starting to get a little algae on them, and the bottom too, I really really want to clean the tank, but do not want to risk losing the fry - their mother died so I am hoping to be able to replace her from this lot. I'm even too scard to syphon water because they are so tiny. Any suggestions would be greatly appreciated.
cheers