other brackish fish??

[Shaner]

So I am appearing to be getting a 65 gallon tank for my GSP's I have two right now, I was wondering if anyone has had GSP's with any other types of brackish fish and if they get along, I looked on live aquaria and found some gobys and of course mollies, scats would be to big as well as archer fish. Can I put a Figure 8 puffer in with GSP's or should I add another GSP?

Or should I just leave well enough alone and create a awesome biotope for the two that are in there now?

Any thoughts

[Roflcopter]

I'd suggest get a single knight goby to go with the GSPs.  This is ONLY a suggestion because I really don't know about compatibility with GSP, considering the size of the tank I'd imagine it'd be fine.

Knight gobys are often sold as freshwater but can fair a bit better in brackish.  Theres a profile in the fish profiles section under Miscellaneous.

They are such awesome creatures, a knight goby was my first fish.  He was about 3 inches long and eating ghost shrimp, idk how but he was.  My heart broke a little when he died.   

Give it lots of places to hide, it'll stake a claim in a favorite hole and guard it constantly.