just make shure you get one from a tropical reigon , if not shure ask the lfs where they where imported from , most lfs will be able to tell you , consider putting 3 or 4 in the tank as they are best in a group , the birchir will be fine unless they breed , what size tank ? , remember the birchir will grow big
also as allready advised belheri are no tankmates for tropical fish ,they will not live long lives with permanent high temps they need a winter cooling period , to be honest the only snakehead i would put with tropical fish is gachua ,and thats only if you really must mix them , the best way to keep snakeheads is to keep a small group of 4-6 . i dont know how attatched you are to the birchir but if you could consider traiding it , then you will have a choice of many snakeheads to choose from - you would not be disapointed
good luck with whatever you choose ,either way iam shure you will love snakeheads , even my wife loves them and she doesnt like many fish at all lol