Hi I have a 56 L planted tank I had originally about 30 rcs 6 black bumble bee, 8 red bumble bee and 10 green shrimps. 3 assassin snails and hundreds of snails. But over about 6 months all I have left is 3 rcs 3 green shrimps and all the snails. My water quality is spot on and always has been. I...