If you use fine sand (play sand), it can and will ruin filters.
If you use a more dense sand (pool filter sand) it will not easily be stirred up.
I agree, when I syphon pool filter sand, most detritus stays on the surface, and I don't need too dig in to siphon it out.
And I also agree with the others, a 55 is way too small for managuense (or any Parachromis for that matter) long term.
Central American cichlids like those from the genus Amatitlania, such as nanoluteus, honduran red point or some other small species like multispinnossa would be much more apropos for such a small tank.
nanoluteus
HRP
myrnae
multispinnossa