tankmates for puffers and monos

Question
I have a 120 (4x2x2) with a 4 gallon sump. I currently have 2 GSPs and 4 monos (two argentinuos and 2 sebae). I would like to add some more fish. What tankmates are good for these guys? 0 ammonia, 10-20 nitrates (working on bringing that down before adding) and SG of 1.2. I would like to stick with fish that don't get much bigger than 6 / 8 inches. Smaller would be better since it would allow me to add more.

Thanks for the help!

Answer
Hello,

Did you typo the size of the sump?  4 gallons is kinda small?

As for tank mates, and your desire for small, well you know anything that iwll fit into the puffers mouth is food??

I like eels and would love to have one, maybe you can fit them into your tank, i also like angelfish.  A nice butterfly perhaps?  

I also like crosshatch trigger but they too are kinda big...

But selecting fish is kinda personal...And i have a community tank, so aggresive fish is not my specialty.

Good luck and please let me know what you end up with??

thanks


Bill