Firstly Sondan is right about the butterflys and barbs, butterfly fish have long delicate finnage which is like a red rag to a bull for barbs and once stressed butterflys rarely recover.
Convicts in a non cichlid community is a deffinate no no, for there size they are highly aggressive and if they start breeding only get worse, your other fish just wouldnt stand a chance.
Which species of bichir do you have? If it is anything other than a senegalus then your shark and tiger barbs are in trouble of being eaten once the bichir has a little size on it, long thin fish and those under 3" make nice meals for bichirs.
