The blood parrot will be fine. I read the whole thread but I would just like to add that if you must insist on getting one of the three aforementioned fish, the knife fish would be by far your best bet. The tanks is too small but it is the best out of the choices. The arrow will get too large and is too active and the catfish will likely bust out of your tank in a few years. I also see in your sig that its has an asian rtc...whatever you do, don't do this. They are among the most aggressive catfish and will almost definately kill all of your other fish in a years time or so.
IF you like catfish, a lima shovelnose would be a good bet as well as a megalodoras irwini, if it happens to outgrow your tank then it will be highly desirable at that size as compared to a rtc which you couldn't give away for free if you tried, atleast around here. As for other compatible fish, a fire eel, maybe a school of clown loaches, bichirs, silver dollars ect...