125 gallon tank. Ammonia 0 Nitrite 0 Nitrate barely 5 PH 8.2 Tank has been set up about 10 weeks. With my levels I thought I was cycled , however just added 8 tiger barbs from reputable LFS and they all died. I guess my first question is with my nitrates still being that low is it possible that my tank isn’t done cycling and would that cause the death of all barbs? Or is it my high PH? There are 6 Cory cats and 2 spotted Raphael’s that seem to be doing fine. Thanks!