I have had a tank of multi cichlids that were breeding in the very beginning, when there was just one male, one female and a lot of shells. I now have 10 fish, of varying sizes; two large males, two females, and a scattering of small-to-mid-size juveniles. (I got the juveniles from GSAS; unfortunately my fish haven't been reproducing for over 8 months). There are forty shells in total; I divided them into a few different groups based on the males' territorial behavior.
tank size: 20 gal L
pH: 9.0 at the beginning of the week, falls to 8.2 by the end of the week before water change
temp: 78F, it is set at 80 though; perhaps I should get a new heater?
fish: 10 Neolamprologus multifasciatus of varying sizes
#shells: 40
nitrate: 0 ppm
diet: omega one marine flakes, a tiny sprinkle of Hikari first bites (a fellow multis keeper told me that having baby food around might encourage babies), frozen bbs weekly
~one airstone bar for oxygen and current
~the thermometer on the fourth picture is broken; the temp is actually 78F