5g Stock

I would suggest zebra danios- but they require a bit more room than a 5g would allow- so white clouds are the probably the best.
 
You could always put 2 male guppies in with the ADF's. Or some male endler's livebearers, but they're hard to find. I fyou really like Endler's though, you can contact John N. in the Classified's section. He sells them at good prices.
 
try a betta and an apple snail, or 4-5 white clouds or neons.
 
I would not recommend neons for a 5 gallon. IMO, 10 is the minimum. However, my recommendations are as follows:

4-5 White Clouds
2 Male Guppies and 2 ADF's
4 male Endler's and 2 ADF's
1 Male Betta and some Ghost Shrimp
1 Dwarf Gourami and some Ghost Shrimp
A pair of Cherry Barbs
 
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