For all these fish I would say 250g...except for the RTC. But thats just me. Some people think its okay to have one of each in a 220 together as long as they are all young fish, others say no way to any of them and still others say just a couple as long as they get along together... All the fish mentioned are aggressive in their own right and all get very large. I would use common sense and really try to evaluate each on its own. A catfish will sit on the bottom and not need to thrash around like an Aro or Peacock. A Pacu will hang out in the middle like a Gar and just kinda sit there. The Aro will constantly move around and are very skittish, so a big space is needed for swimming. I Clown Knifes and Bichirs arent really known for swimming around alot either.
Put it in this perspective...a Cadillac will fit in a single car garage and be safe and secure, but forget keeping it from getting door dings. Even a two car garage wouldnt allow you to service it comfortably. A Honda in the same space, thats more realistic. Neither car can turn around inside the garage though, so maybe a different storage option is advisable, especially if the Cadillac and the Honda are prized collectibles.
