I have 2 neons that have been doing well for a while.. The one seems to be swimming sorta on a angle.. Physically looks ok still eating...tested tank everything within spec.at night it seems normal and just hangs with the other tetra. It sorta been swimming like on that kinda angle.. Ph is a ill high 7.5 kh is 240 I just moved them to a 5 gallon it sat for 2 weeks but it was swimming that way in the other tank.