Sup guys. I've been in this hobby 10 years now. I have African setup over 2 years with 7 bumblebees, stratus, blues...etc. I recieved 4 large Africans of the same on Saturday. Woke up Monday to a complete crash...everybody died. A blue film haze overcame the tank. Water is slimey. I've never seen this before. Only thing I can think of is some of the water i got the fish in mixed with mine Same food, nothing different. Sunday they were fine as well. Maybe a bacteria bloom that was deadly. Any thoughts?