I am not sure whether this is brown algae or diatom ?? I have done several water changes and used different buckets to replace the water and it keeps comming back !! I tried red slime remover because that is what I was told it was. It is brown or golden brown substance that covers the rocks and is in splotches on the glass and is now growing on the hermit crab. I have took out all the ornaments and bleached them and scrubbed all the glass and cut back on the lighting and feeding and it just keeps comming back after a week. does any one know a way to treat and get rid of this whatever ????