My Puffers: 1x GSP (Bolla), 1x m. something. Bought as a leiurus, maybe a turgidus (Tiger), 1x c. irrubesco (Tott(a) aka Houdini) 1x c. salivator (Jack the Ripper), 1x m. cochinchinensis (Hufflepuff - R.I.P.), 2x c. lorteti (Tommy and Tigern = Calvin and Hubbes), 1x m. suvatti (Koseklumpen), 1x m. palembangensis (Dragonfly), 2x t. biocellatus (Koken and Fiken).
There is a puffer very like the lorteti that is not aggressive, google it to make sure this one is a lorteti. I have been told that lorteti can be kept in pairs but when I tried it one killed the other unexpectedly after a period of relative peace. Don't try to keep them with any other puffer!!!! They tried to tear shreds out of my F8's who didn't know what hit them! Thankfully they were too small to do any real harm. I had acted on advice (on the net) that they were peacefull later I found out that confusion had been made between lorteti and the one I mention above, can't remember the name. Looking back I should have known as they were about 50 of them constantly bickering in the tank at the LFS from the first day they arrived. Watch the tank for five mins , if there is no nipping going on I find it hard to belive they are the same as the fish I bought.
I think my biggest mistake was that the tank was not large enough for two. If you want to try a pair I'd say you might just do it with a really big tank with lots of hiding places and a sand substrate. They are teritorial so if they had space for each to have it's own territory it might work (?). I belive they have been bred in captivity. Keep them well fed. My problem came when I was away for a couple of days and I think the hunger tipped them over the edge.