I have two established tanks in my basement that I clean like clockwork each week. One thirty gallon and a two twenty. Both have had a fog grow in them within the past two weeks and I am pretty sure it is as bad as it's ever been. My question is how? Could there be an issue with my hose water, or maybe some kind of nitrate spike? Possibly some issue with heaters and the warming weather? Either way its strange and any advice to help me clear it up would be appreciated, I can't stand looking at it anymore.

