Hello, My name is Loren, user name Guppy. I am currently between tanks but have run many over the years. The last two predator tanks I had were fairly small,1@35 gal., and 1@55gal.. The 55 held an African Pike Characin (Phago maculatus) about 8" long, a Whitespotted Pike Cichlid about the same size, and three Acestrorhynchus falcatus Barracudas that were also that size. There were several cory cats in it as well. The other tank held only one fish and was not planted or even heated. It contained a fish that was given to me as a Marbled Sleeper, I don't know it's genus or even family but it was a monter that grew from 10"s to 14"s in one year and once ate a largeouth bass that was an inch longer than it was. It sat around for tree days with the basses tail sticking out of it's mouth. I am looking forward to starting a tank or two soon