I've just read about Bala Sharks and they need a 50 (at adult size) gallon and seem suitable. They are quite spooky and need suitable tankmates. They are nicely coloured. They need to be kept in groups of preferably 2 and up.
Lucy (only beginner correct me if im wrong anyone)
Heres some information from a site :
The Bala shark is simply a cool fish. They look like miniature sharks with their silver coloration and tall dorsal fin, even more so than other cyprinids known as freshwater "sharks." They are peaceful fish, despite their large size, and they can even be kept with small tetras and guppies.
Balas are fast swimmers and may take a while to settle in. They can be housed temporarily in a ten gallon tank when under 4 inches, but please move them to better quarters ASAP. I listed the requirements for tank size as 45 gallons, but they are best in 55 gallon and above aquariums. If you do squeeze a bala into a 45 gallon, keep only two and give them plenty of plants, plastic or real, in which to hide.
These fish are nearly as popular as cory cats, and unfortunately, they get sold to people with ten gallon systems who just don't know better. These sharks grow much larger than the other sharks, like rainbow and red-tails. They are also peaceful and would not go well with aggressive red-tail and rainbow sharks, unless they are in a massive tank.
Balas make clicking noises when they eat. This is startling at first, but soon you come to love it--and you start to think something is wrong when you don't hear it! They also have a fun habit of sticking their entire heads out of the water when devouring food on the surface, just like great white sharks.
