Normally they are not compatiable, especially when one is established already in the tank. I have only pulled that off once and they went in together as babies and turned out to be male and female. If you look you never see 2 Puffs in a tank at a lfs for good reason. You might consider something like a Dianas Hogfish, or even a larger Angel if you are into Angels. The only Puffs I have (out of 5) that have any tank mates are the 2 Porks pair and they have a Dianas and a Rock Beauty Angel in a 120 gal tank. The other 3 Puffs are by themselves (2 are babies a Dog- A Pork, and one is a very very large Dog who hates anything that swims in its tank).