Black shark in fluval edge 6gal tank

[ESMC2009]

Hello

I purchase a fluval edge 6 gal tank 2 weeks ago. Nice tank but its small. I purchased it as a starter tank to keep for a few months. In it I have 4 neon tetra, a black shark, I was told that the black shark about 2 inches long was going to eventually grow and eat all my other fish. So far he has been behaving stay at the bottom of the tank and pops up a few times here and there. I wanted to purchase a 55gal tank to transfer him into, but to also house some other fish. Does anyone have a black shark, and would it really grow and become aggressive?

[Cliff]

Is this the black shark you are talking about:

http://aqualandpetsplus.com/Shark%2C%20Black.htm

If it is, than I would return it to the store. Even a 55 gallon tank is way too small for a fish that gets over a foot long

[ESMC2009]

Yes thats the one. That sucks I really like this black shark. So is that a myth that fish grow according to the size of the tank?

[Brhino]

Yes and no. It's true that a fish will grow less in an undersized tank, but it's called stunting and it's very bad for their health.

[Lady Hobbs]

You want your "soon to be" 2 ft shark to only grow 4" so he can fit in your tank?

Give the guy a break and get rid of him so he can have a real life in a large tank. Your store should not even be selling fish that grow that large.

[ESMC2009]

Thanks for you hel[ Cliff and Brhino, I m returning him to the store today for another fish. Thanks again.