OLDER CICHLIDS

If your guys are stable at the moment, sit it out and wait for the 55 before adding more fish - a stable mix in an african tank you should be really slow to interfere with, even in a big set up. Anyway at least you know they're going to need the 55 - sooner rather than later, and then you can really increase your stock.
i wont get more until the 55 is ready, there will be a max of 10 inther, but way over filtered so i think i will be fine

they'll have a 75 gallon in about a year, if i have the money, but a 55 will do, im not like those other that stock 20 of them in a 20 gal tank
 
You can have a couple more in a 55 - over-filtration is absolutely the way to go.
 
AquariaCentral.com