Hi there folks.
I've got a 60 gallon tank containing a Red Devil ( William ), and a marbled knife fish ( Denzil ). Between them they have eaten 3 black sharks, 2 firemouths, 2 bala sharks and a pictus cat.
I thought it would only be a matter of time before I'd be left with one supreme tank being, but to my surprise William and Denzil get along just fine. I have caves set up either side of the tank which I think helps as Denzil is a nocturnal predator and without somewhere to hide and call home he gets restless and grumpy. William, the red devil, just watches Denzil, as if fascinated by his swimming motion. Every now and then they face up to one another in the center of the tank but not once has there been any conflict - more a sense of masculine respect between warriors.
William is 7" long, Denzil is 10". I'm hoping, praying that William, despite future growth and increased levels of aggression, will continue to see Denzil as a friend not a threat.
But as many of us have learned and are still learning - this hobby is a costly but fun game of trial and error.
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