What kind of rocks are those? It looks like granite, quartzite or arkose. I thought africans had to be on calcerous rocks. I dont know for sure, that's why I'm asking.
The idea is great, you just need to use bigger bolders and have more space in between, otherwise you'll have way too much detritus gathering under those rocks.
Oh, I also had a question: I've seen some people that come into my shop with african and SA cichlids in the same tank. I didnt think that was appropriate; anyone know?