In a word, no.
300 litres is a good size, but not a gigantic tank. Some of these fish are gregarious; you don't keep one tinfoil barb but a school of them, and realistically that means at least 375 litres. Fire eels are difficult to feed and even keep alive, and
Steatogenys elegans is far from easy, requiring fairly cool, oxygen-rich water similar to the fast-water streams it inhabits in the wild. Both make sense in single-species settings, possibly with other, carefully chosen tankmates added ONLY when the the eel or the knifefish are feeding and settled.
Ctenopoma acutirostre is a nice fish comparable to an angelfish in temperament, and will be taken apart by
Hemichromis spp. Bichirs are easy targets for aggressive cichlids.
Synodontis multipunctatus needs hard, basic water and middling temperature; it has no place in a tank with soft water fish.
Thanks for the advice but which of the fish out of them can i mix?
Cheers, Neale
can i mix these fish:fire eel, syndontis multipuntus, polypterus palmas plams, ctenopoma leopard, elegant knifefish, tinfoil barb, jewel cichlid, snakehead assam lal chag.
PS: my tank is 300 litres