KokeMachine wrote in to let us know about a video he took of a strange looking rainbow trout, and wondered if anyone knew what caused the white fuzz all over it’s body.
Well, having nearly 150 gallons worth of aquarium space in my house I can tell you that this looks like a fish with very serious case of Ichthyophthirius Multifiliis, more commonly called ‘Ich’.
Visible Ich lesions are usually seen as one or several characteristic white spots on the body or fins of the fish. The white spots are single cells called trophozoites or trophonts, which feed on the tissues of the host and may grow to 1 mm in diameter. A smear should show ciliates if white spot is present.