Single freshwater puffer in a community tank?

[Maxwell09]

Hi, I have a 40 gallon tank, 75cm x 45 cm x 45cm, or 30 in x 18 in x 18 in. I was looking for a species of puffer that could be kept as my centerpiece fish, housed a long with a few tetras and bottom dwellers. I have read that most of the, "peaceful" puffers need groups, so I would like to confirm that with all of you.

Thanks!