I thought they were on your list of unwanted fish.Whats minimum for puffers?
They won't chase like a snakeheadthat is not a puffer
Pea Puffers can be kept singly in less then 10g, a male with three females in a 20g.
A lone mbu would need 800+gallons with at least 3ft of width and depth.
There are many puffers between these two.
(I have never kept puffers)