Hi,
I have a well established AR-850 [160 litres] with a variety of small fish, 2 Zebra Danio, 5 Silvertip Tetra, 8 Black Neon Tetra, 6 Cherry Barbs, 2 Peppered Corys and 5 Diamond Head Tetra.
For the past week or so 2 of the DH Tetra have been behaving in a strange way, at first I thought they...