I checked out the website you listed, and the electric yellow is in fact a labidochromis caeruelus, the electric blue is a Sciaenochromis fryeri.
The bad new is that l.caeruleus is one of the herbivorous mbuna (rock-dwellers) of Lake Malawi, and the s.fryeri is a carnivorous hap (open water) of Lake Malawi. It is very difficult to keep the two kinds together for several reason, they have different feeding requirements, while l.caeruleus can handle a little more protein in their diet than most mbuna, the amount that the s.fryeri requires can lead to the l.caeruleus developing bloat; mbuna are also far more aggressive than haps, however haps generally grow larger, and if they reach their full size without getting killed, they can turn the table and kill the mbuna; mbuna live in rock caves and crevices in the wild, and need a lot of rockwork to feel safe, haps prefer open water, and need the room to swim, so a large tank is necessary.
I don't mean to sound so negative, but a lot of research is necessary to keep african cichlids successfully long-term. Please take a look at that article from my first post, and cancel your order if possible, until you are sure you can properly house and maintain the fish.