I voted with the cories personally.
My VT is in a 15g with cories and young pic.cats.
I have a filter, but have cut the current down with heavy planting.
Mines as happy as can be, and spends a part of each day 'hanging' with the cories. He does on occasion flare and chase them around, but since its rare and he never bites them etc Iv gotten the impression its more of a male pms feeling.