I've tried to put algee eaters in the 29g tank with my red devil, but he kills them everytime. Is this normal, or is the size of the tank an issue? Also he keeps picking up rocks in his mouth and moves them to the other side of the tank.
some red devils are mean and some are not as much. i had one that got pushed around by a blodd parrot an inch shorter but you got a mean one that needs more room becaue they require atleast 55 but prefibly a 75 gallon. he is moving the rocks becasue he is territorial.
You probabaly wont be able to have tank mates with him unless you plan to put him in a 100g or larger. A 55g is min. for a female and 75g for a male. In a 29g he will kill anything you put in there with him except for rocks. A lot of Cichlids are diggers and it's normal behavior to move rocks as he's setting up territory.
i had two big red devils in a 6ft /2ft/3ft/
and the only ones they never touched was the brissle nose cat fish as they are ment to know that they are toxic