Green Spotted Puffer Question

How large is the tank? I have 2 GSPs (5") & a ceylon puffer (3") living in a 45g tank. It also depends on the puffers themselves. One can be a pit bull & another can be a pussycat.

GSP seem to do best in mid to high BW or even SW, hold their color and grow to full size. They are more likely to be aggressive to tankmates than any other puffer in their size range, but individual variations from puffer to puffer are unpredictable.

Figure-8s are only half the size of GSP, seem to do best in light brackish, and are not (generally) as waspish as GSPs.

Not a good combo IMHO.

A GSP grows to 6" as an adult. A 20gal is barely large enough for one fish. I started mine living together small. They seem to be getting along fine as larger fishes. I think part of the reason is the larger tank they're in. Also, lots of hiding places & broken lines of sight.

The LFS I go to all the time has figure 8's and GSPs together in a tank and they've had no problems but I guess the salinity does become an issue. You're better off putting something like scats, monos or archer fish with your GSP.

What the LFS can get away with short-term with juveniles, and what a hobbyist can do with adults during the puffer's 15-20 year lifespan is likely to be quite different. They do have young Jack Dempseys and Red Terrors together also, don't they?

Monos are schooling fish, scats grow as large as your outstreached hand. Neither will fit in a 20g.