hello i have a 4 inch stingray that ive had for about 2-3 weeks and who hasnt ate at all and have been breathing super heavy the whole time and been sitting prety much in one sot with out movement. my water chem is ammonia 0, nitrite 0, nitrate 20, gh 150, ph 7.2. now honestly i dont know anything about rays, the one i have is a teacup which im told is a smaller breed, but aslo more sensitive but im confused bc i know there from the amazon so they need soft acidic water, but i was told by the owner of my lfs that theyneed salt and high ph and gh, bc they originlly came from salt water areas, sounds suspisious bc sense there scaleless sensitive fish i assumed the salt could burn them but idk, would love some clearity on this and any thoughts on my my fish is sad and prob about to die, thanks