What fish can i put in with my figure 8 puffer fish?

Question

in a freshwater tank.

no, they are not brackish so dont try saying that.

Answer 1

They might not be in brackish water as juveniles but as an adult they need low-end brackish.

You might be interested in this:

http://www.thepufferforum.com/forum/ug.p...

As for tank-mates, I wouldn't chance adding anything with them. I wouldn't put any tank-mates with any of my puffers just because of temperament and territorial.