What should I get?

I would like to add some inverts to this tank but I don't know what to get. I have some Cherry Red Shrimp in one of my other tanks and Rili shrimp in another so I'd rather not get more of either of those. Here's a picture of the tank. It has one Gold Gourami, 9 kuhli loaches, 1 nertrite snail and some trumpet snails.

20 gallon May 15 2013.jpg

20 gallon May 15 2013.jpg
 
They need brackish water in order to be able to breed. Just double checked to make sure I was thinking of the right species. So if you buy 6 you'll only have 6 cause they won't be able to multiply in fresh water.
 
AquariaCentral.com