I have a 100g tank that has been running since 17th September with several species of Mbuna, most in groups of 5 but was unable to get more than 3 Cynotolapia Red Top Afra. Ironically these were the ones that bred within weeks of the tank being set up. The tank has loads and loads of rockwork. also in the tank are 6 Synos, a blue Moori and a Venusti but the buggers still want to breed.
I recently had to remove almost all my rock work and purchase a new tank just to house some of the 30 juvenile afras I now have, the female afra is currently holding another batch, as are 2 of my Perlmutt and a yellow Lab.
I never wanted them to breed, and since having juves I have never fed them anything they have just scavenged what sunk to the bottom and hid in cracks between rocks until big enough to get away with snatching pieces from the middle of the tank, and despite the presence of predators in the tank they still thrive.
So maybe if you actually want them to breed, firstly be careful what you wish for unless you like spending hours up to your elbows in the tank. As for conditions.
My tank was fully cycled before fish added and my water is pH 8.4, Temp is 26 degrees, water is 20 ppm of Nitrate from tap, Ammonia and Nitrite are 0.
I have an FX5 canister and an internal U4 giving about 12 times cycling.
The tank gets very little natural light. I use one light bar with 2 bulbs one powerglo, one marineglo, 40w T8 on for 5 hours a day.
I feed a mixture of Nutrafin Max flakes, Tetra Prima and Tetra Pro Vegetable and Algae wafers.
I think the secret is probably lots and lots of rock with lots and lots of nooks, crannies and caves.
So these would appear to be the ideal conditions despite my sincerest wish that they weren't
