FW Puffer with BGK?

[Stump]

I recently bought a 40 gallon breeder tank, and will be starting to cycle it in the near future. I bought it mainly as an upgraded tank for my 5" Black Ghost Knifefish, but also because I love the idea of choosing new, interesting fish. I have contemplated South American cichlids, and have felt strongly about going that route, but I still have that curious urge to get a puffer or two. I have kept a brackish puffer before, it ended up getting sucked into the filter after I stupidly forgot to put the end on it. Anyway, are there any Puffers I could keep with the Knife? The tank has a 3' x 18" footprint, and is 16" tall. Any advice, or suggestions would be great, and appreciated.​

 

[Pufferpunk]

The SOUTH AMERICAN PUFFER is from the same region but still may nip on the sedentary BGK.

 

[Stump]

I was thinking about those... How many could I keep in there?

Trimming their teeth would have to be done how often in your estimation?

 

[random fish guy]

i have a 120 gal stocked with mostly cichlids, a few green puffers, and plecos. at first had some problems with fin nipping, but that has seemed to stop. I would be a little weary of keeping a BGK with a puffer though

 

[Pufferpunk]

RFG, GSPs belong in high-end BW, not FW.

I find SAPs needing their teeth trimed every 4-6 months, depending on how many snails they are given to eat. More difficult to feed snails in a large tank.