Hi there... Peter has given you great advice.
I highly recommend the combo of rams/boivian rams with geos.. The tank size is gonna determine which and how many. geos. really the footprint rather than the gallons..Is a 50l 4 feet long or five feet long?? Basically everyone is gonna want their share of the floor but if aquascaped well you should not have any problems.. I recently added some blue ram pairs to my 120 4x2x2 orangehead geo and angel tank and everyone gets along very well. I've also recommended the bolivians as a combo to others.. the difference mainly being the preferred temps for the bolivians being lower than the blue rams.. Good luck whatever you decide to do and pics please
Sue. (another out of the closet geo addict)...

Sue. (another out of the closet geo addict)...