not necessary imo.
The Cichlid buffers contain a mix of ingredients designed to replicate the rift lake conditions...(Ph, Kh, Dh, dissolved mineral content).
Fine, except that these fish unless wild caught have been born and reared in breeder tanks then kept in LFS tanks which are not maintained at those parameters, generally. Of course, you should always enquire as to whether these buffers are used by your supplier, in order to do a proper acclimitisation.
I am aware that a lot of people will say they use them and have great results which I'm sure is true; I just don't think they are necessary and prefer stability in my water parameters, rather than trying to match a notional ideal by adding chemicals.