I have a 60 gal that has been setup for over a year that has an ornate bichir, endli bichir, gold severum and a ntt datnoid (all are young and I have a 210 gallon tank that just needs a few things before I can start setting it up) and it seems it started a crash with really bad timing. It all started Wednesday with the datnoid not wanting to eat but still active this continued until friday night which was when i noticed the datnoid wasn't as active and had white spots on it I assumed it was either a fungal infection or ich, then Saturday I did my normal 30% to 40% water change while doing so I hit a small gas pocket in the sand which I didn't think much of until I was starting to refill the tank, I noticed the datnoid was sitting on the bottom on his back still alive just sitting there, after the tank was refilled it would stay on it's back or side for an hour to an hour and a half then started swimming normally while every once in a while laying down again for a while which has continued since then. Today I tested the water to see if maybe it might be a tank crash and the ammonia and nitrates were through the roof but nitrites were zero. I have ordered some salt and medications for the fish and plan to do water changes daily or every other day. I would appreciate any advice i can get.