Ibelieve you would have abotu 5 years before you would absolutely need a larger tank...
My opinion
To answer your question.. Monos and intermedia may fit.... But as for housing for the total expected life range.. No.
You will se after they get larger taht your opinion will change do to your feeling on how they use the space and really do need more than we give them. That too is just my opinion.
The answer to this question depends on how comfortable you are with keeping 20" fish in a tank that is only 24" wide. If you are okay with that, then monos, occelaris, and intermedias would work.