Take the fish out and put in2 a bucket.The new water must be aging ( bubble up the pipe water to removed the clorine,no anti clorine.Then check whenever the clorine is still present).

After put the fish in the bucket .observed the poo.If it's black,might not be indigestion.if white then it's indigestion.This technics can be done in an aquarium oso.Air must be supply.for the best result put the fish at least one hour.hope that help.

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We Keep CICHLIDS , We Don't Behave Like CICHLIDS !