sera guide - Healthy aquarium fish

Uniform darkening of the entire fish Cause: Feeling unwell, caused by unsuitable or polluted water, or by not keeping the fish according to their requirements (e.g. no hideaways, keeping unsuitable species together etc.) Treatment: page 41 Observation Pale colors or, in some fish such as Discus, uniform darken- ing. Cause: Injuries, e.g. by catching with a coarse net, transport injuries, injuries by trying hectically to escape (bouncing into sharp edged decoration objects) or by territorial fights Treatment: page 41 Observation Mucous membrane rubbed off, skin injuries. Large-area injury on a Discus 4 Maintenance mistakes and intoxications 22