Hi Chenay, welcome to Fishlore. the Tropheus Moorii Lufubu "Purple rainbow" is from Lake Tanganyikan and one of the beauties of the African Cichlids. your 55gl would home a breeding colony well enough but should be a species only tank. they have been known to share space with some victorian species and the like but you need to do your research well to make it work. syno's go well with them for a cleaning crew as well.