hi, thanks for the advice, i shall look into the ph side of things. My tank is 120cm x 40cm x 40cm, not sure how to work out the volume in gallons. I have 24 adult chiclids four of which are yellow labs, i also have 8 baby johannis as they breed like rabbits, they seem to be trying to re populate the world all other fish seem fine, they are quite aggresive in the mornings but calm down after their morning feed.

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