For life that’s a decent tank for Kelberi and maybe a smaller farmed mono. For a growout you could keep intermedia, mono, kelberi, and orinos in there for ~2 years before needing an upgrade from what I’ve seen in their growth rates. Your width is ok they just realistically want more running length. Still, Kelberi are some of the most gorgeous fish out there if you find the right ones. You could grab a school of 8 babies and sell them off as they grow to make your money back till you have 3-4 or a nice pair.