Hey everyone, in about a few weeks, I will be helping my friend set up a 55 gallon aquarium. He is mainly interested in getting bichirs, the bichirs he want are endlicheri, albino senegal, and senegal all about 6 inches or less, for the fish tank but would also like other fish. The other fish he is planning on getting is a pair of frontosa (4 inch), a pair of parrot fish (4 inch), a black ghost knife fish (6 inch), and a fire eel (8 inch). Will all these fish mix together without any problems with aggression? Are there fish in the list that will be a problem with each other? What are some other fish that can go well with the list? Do not worry about the tank size because I know the fish will outgrow the tank, at a certain size, my friend will give me the fish to put in my 180 gallon. Thanks for everyones help 
