

Kuhli loach turned white?!
I have 5 kuhli loaches, I've had them for about 4 years . 3 black and 2 striped. I noticed today one of my striped ones is WHITE. None of my others have pigment loss. Unfortunately she came out after a water change and I didn't test the water beforehand. There are also corydora catfish in the tank - 20 gallon long planted with sponge filter and heater. Substrate is mostly sand with river stone. Pic of her normal color included. What is this??