So this morning I went to look in my 10 gallon tank with 6 tetras and one of them was barely moving but still breathing at the bottom of the tank and the other ones are lively like usual. The one on the bottom only has color on his head and tail fin. The water parameters are good but the water may be too hard for tetras. The other neons have a few white dots. And there are two kuhliI loaches in the tank as well. Is it ick or neon tetra disease or something else?