Carapos are larger and aggressive. Centipede knives could be tried and more than one can be kept. The BGK would have to be watched with them.
Elephant knife fish would be a great pick up but better in a solo tank. They are very territorial and may not eat because of fighting fish for territory.
Yea there are 2 centipedes and they are 6 inches but that reallly tips me off cause he special ordered them for me and they are carapos man I swear this is like the third time this has happened to me haha well I am just waiting till I can find a real one but thanks for all of your help