I just bought a 8'x3'x2.5' 450 gallon tank. It will have larger more robust ca/sa cichlids--Midas, fh, gt, creni. Sveni, jd and cons. Is there a cat that tops out around 15-18 inches that I don't have to worry about eating my cons--probably the smallest cich. in the tank? I have about a 6" syno in there if that makes a difference. Fairly inexperienced with cats and all advice/suggestions appreciated. Thanks