I just searched for hardness using a business based in Fishergate, Preston. United Utilities gives their hardness as 6.93 Clark which equates to 5.5 dH and 90 ppm. Way too soft for Rift Lake cichlids.
If your hardness is similar, you'll need to add something to make your water harder if you want to keep mbuna.
If your hardness is similar, you'll need to add something to make your water harder if you want to keep mbuna.
