Muddy water this spring. Diffuser stand had tipped over. Fixed that.
Did a jar test. Didn't look terrible. After a week of sitting it looks like tap water.
Well, tap water with bugs. Lots of teensy weensy little swimming critters.
So I've shut off the air pump. Hopefully it will clear a bit over the next couple weeks.
Only way to find out is to wait and see what happens.