:sad My 20 gallon tank: 2 male platies; 3 neon cardinals; 1 cory cat; 5 ghost shrimp and then 2 danios. The zebra danio chases all my fish, the first one, one of my 4 neon cards, he chased exclusively, then the cardinal died. He started chasing all the cards, now he's chasing my platies. My platy is chasing the other platy, especially during feeding time, and even the cards are chasing eachother! Readings: 0 ammo; 0 trite; 7 PH, ? trate (kit malfunctioning, but had water tested last week and lfs said it was good). Any ideas?