My new 16"

[jbarbaresi]

I don't know what that is. My pleco seems happy and does what he/she should be doing: Rasping half a cuke or summer squash every day, swimming and munching microbes off the plastic plants in the tank, ignoring the Red Devil cichlid tankmate that thinks it could own the tank (Pleco is not fooled, he/she knows that that Cichlid's clock would be cleaned with one swipe) and enjoying perfect water from her Eheim canister filter. She's a very mellow fish with perfect water and cool markings.

the term "stressed coloration" doesn't necessarily mean your fish is stressed. my p. gibbiceps shows that pattern most of the day when he is resting on the glass or in his cave. it is normal and you will probably notice when he is out swimming and feeding he darkens up quite a bit.