Can someone help me to identify this algae or whatever this is? Does someone know how to solve this problem and what is the cause of it? I've noticed that this algae appeares on the slowgrowth plants as Microsorums and some Crypts,as well as on the substrate where water circulation is the strongest. This white on the leaf is composed of plenty pearls which under hand seems to be hard and grow to the leaf. It is possibly to remove it mechanically,but it is not so easy. Parameter of water: ph 7; kh 11; PO4 1,5 ppm; KNO3 10 ppm. Here is the picture!