Bala Sharks? Alot of questions...

I also agree with not getting the balas for that size tank (125g minimum for adult balas). You could do the scissortail rasboras, as previously mentioned. Avoid tinfoil barbs as they also need a much larger tank. For a bottom dweller you could get a lone rainbow shark or red tailed black shark.
 
1 or 2 red tailed sharks are nice and take quit a few years to really grow out a 55 unless they get comfortable in it and then they will adjust
 
1 or 2 red tailed sharks are nice and take quit a few years to really grow out a 55 unless they get comfortable in it and then they will adjust
Fish don't "adjust." They become stunted.
 
I have one, he hasn't grown in the 4 months I've had him in my 50g. I wouldn't get them, every time I look at the tank I think about how that shark is going to have to go and it's kinda sad :(.
 
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