I talked to the breeder that sold me my Pink Tilapia frys, five months age. Fish turning gray is called "blue belly" or in my case the whole fish, just something that can happens...those fish have more of the blue tilapia chromosomes.
DEAD FISH is probably do to several conditions; Metal toxin might have weaken fish and done some gill damage, 95% water lose on top of that was major stress, water temp at 64 to 66 is OK, but not so good for a traumatized fish.
He recommends treating the water with fish salt but says trying to catch & remove fish would cause more stress and make things worst. Salting my whole AP system would work but would rather not have the salt in my GB's. Anyone who would like to comment on this, it would by appreciated.
He knows of a breeder that slices Oranges right across the equator ( thin slices ) and puts them in the FT. They float, fish eats out the center area, remove after 48 hours.
So not as bad off as I thought I was, no decease, water good, I just have 4 or 5 depressed fish that are not eating well.
Bought some of the original fish food from the breeder, smaller and easier to eat (he has it shipped in form Missouri).
Got home and found one of the pink tilapia dead, fish was on the bottom of the tank not eating just 3 hours before. I notice that the fins on its back was standing straight up, first time I ever seen them do that.