I dont know, i know people that keep them at ph 7 with success.
there are likly other options though. Tetra or barb type would be based on size of the tank also. cherry barbs might be ok, not sure, oto would be fine though.
I read somewhere ottos were the only thing 100% safe, but unsure of that at all... I may just buy a 10 gallong and stick with rabbit snails and shrimp and any other invert or whatever I can add and make it an invert tank.
(It also said anything that had any type of carnivorous diet could eat them)
I'm kind of wanting to do a 3 species shrimp(Been looking at the cross chart and one of these will be the bamboo shrimp or vampire shrimp filter feeders) tank plus otos pygmy corys and maybe the tetras then. Not sure if a pleco is compatible with the otos? Or does this sound like too much of a stock? Lol