Right now I have a 20 high with a bunch of wisteria and some java moss strands that I just can never seem to completely get rid of, and I'm wanting some contrast. I don't want to get a million different plants, which looks great don't get me wrong. I just want a single plant that can be my pride and joy for years to come. The tank also has leaf litter in the front, hence no foreground plants. I'm looking for a darker green plant, and if it has a little red that's fine, but I want mostly green. Eventually I'll get a 3 foot tank, but I doubt I'll ever get past a 55.
So the two ideas that seem to appeal to me the most are amazon swords and bulb plants, and both have flaws. Amazon swords are the ideal color, no dormant phase, nice contrast, but they eventually get MASSIVE. Bulbs however, don't have the exact green I'm looking for, weird as that sounds, but aponogetons have always been near and dear to me. However, I don't like that they melt and go dormant. This could be somewhat combated by planting one every 4 months til I get 3, so I'll always have at least one growing, but I'm not sure that's a good idea given how large they can get.
So I guess the long story short is are there any medium size swords that stay a max of 20 inches, and have a vibrant medium green color, or are there any aponogetons that can mimic this, pr any plants in general.