GOBY!!!

You could try bumblebee gobies but they need to have brackish water.
 
BBGs are every bit as freshwater as they are brackish. An easier freshwater goby to breed though would be Desert Gobies.
 
A lot of places seem to be selling them these days, since they seem to be in some sort of resurgence in popularity. Try checking your LFS, eBay, Aquabid, etc.
 
Another closely related interesting fish would be the peacock gudgeon. Much the same behavior, just the fins they use for suction aren't fused, basically.

normal_gudgeon.jpg


Stiphodon elegans is another awesome little goby that actually eats algae, when you can find them available. I have no idea about spawning those yet though. Right now they're just working as janitors in my 92 corner tank ;). I'll let you know if I see them acting like they might get frisky!

Barbie
 
Stiphodons are one of the many freshwater gobies that needs either brackish or saltwater as part of larvae development. I don't think anyone has tried breeding them in captivity yet, but it could be worth a shot.
 
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