Fish keep on dying. Need help .

[dj ze]

if you had toxins you wouldn't have any corals left or fish you still didn't answer if you observed the fish eating before purchasing them tangs are very stressful fish and the only one i would do for the size of your tank is the kole the others need a much bigger tank have you tried anything else besides tangs

 

[Arnaldo24]

Is 2" thick.