its already a problem
africans like hard water, with a ph of 8.5-9.0 where as goldfish like it at 6.5-7.0 either way, one of these species is suffering
any way you can put the goldfish or cichlids into a new tank? or possibly give the goldfish to a local LFS and get a PH buffer?
that would be your best bet..
also..my apologies if im coming off as a prick, no intentions of that, just trying to help