I have 6 Dwarf Puffers, 6 Bumble Bee Gobies and 2 Dwarf African Frogs in
a 20 Gallon Long.

The Bubble Bee Gobies adapted to freshwater during my attempt to induce
breeding. I added the Puffers and Frogs after it became apparent the
Bubble Bees weren't going to cooperate. (I thought for sure the Barry
White records would do the trick) ...BUT...

.. Anyway ..

This link has the best info on the Dwarf Puffers I have found. The
Gentleman is Japanese and his English truly makes his most valuable
information a joy to read.

http://www.rr.iij4u.or.jp/~kohda/en-index.htm