You have to do your research to find out what is causing the problem. Will throwing some
Snails on their help clean it up? Probably. But a better thing to do for the long term solution would be find out the cause. I had this problem when I set up my tank. I found out through researching diatoms that the main causes Are
1. Water quality
2. Water flow / movement in your tank
3. Too much lighting or light bulbs need to be replaced if they are too old.
I found out that 1. I was using tap water which was affecting my water quality and providing nutrients for the diatoms to live off of. 2 I didn't have any water pumps or powerheads in my tank so hardly any flow which led
to dead spots. And there I was over feeding and leaving my lights on longer than 7 hours everyday
Find the cause and eliminate that!