I come look at my tank this morning and I notice pretty much all my fish are hiding. 2 green servums, 1 red servum, GT, JD, 2 blood jewels, and one convict. They were pretty much all hiding and the only ones out were my 3 tiger barbs. Usually everyone is out and about swimming around and come to the front and now they are all hiding. Only thing I did was do a 25% WC yesterday and two days before I added a little bit of aquarium salt because I noticed my jewel was hiding and not moving and now everyone is. I will test the water later, you guys think it could be high nitrates or something bigger?