I understand that clown loaches are prone to the internal parasite that causes "skinny disease". I lost about 6 of them years back when I introduced a new clown loach into my tank. But my question is, can clown loaches all of a sudden, out of the blue, spontaneously contract this (i.e. if no new tank mates have been added). Some of my loaches are starting to look skinny, and my water parameters look good, they've been getting the same diet for 2 years now, in the same 125 gal that they've always been in.
Also, can fish other than loaches bring this parasite into the tank and affect only the loaches?
Also, can fish other than loaches bring this parasite into the tank and affect only the loaches?