I am currently housing two alligator gars and two teacup stingrays in my 75 gallon... the gars are about 5 to 6 inches and the rays are about 4 inches across....i've had the four of them together for about 6 weeks now and they get along really well...what i'm looking for is another tankmate or two that are non-aggressive (no picking at my rays!!!) to add to the mix...i have good plant cover from mid-to-top thus a pretty open bottom for the rays....i prefer something a little out of the ordinary.... any suggestions would be a great help....thanx in advance