Yellow watchman Goby loosing color!

[ChrisL]

anyone know why this may be?

Just noticed today, that my watchman goby was starting to whiten up a bit.

I've had the tank up for several months now, and have been doing 10% weekly water changes. When I got up this morning and saw its color, I quickly changed the water. The Goby's color has not returned. Not sure what else i can do.

The tanks only inhabitants are a tiger pistol and the watchman goby.

Thanks in advance.,
ChrisL

[MikeP]

Many gobies will change colors somewhat as they age or if they are in a mated pair. You could try feeding him a more varied diet and see if that doesn't help - unless he is showing other signs of distress it may just be an environmental stressor and not an illness.