Good info Brian,
I haven't kept them before. I guess I've just gotten lucky. I usually leave my breeding fish in bare bottom tanks. I also do partial water changes on everything except fry tanks once a week. My fry tanks get water partial water changes twice a week.
With the Rams I keep the temp up around 85 and TDS low. Nice soft RO/DI water.
I had a spawn mid Dec and then another 3 weeks later. I also talked with a breeder friend of mine and he also had routine spawns every couple weeks. They are also the only dwarf except the Neo/lamprologus type that will actually attack my hand when changing a sponge filter or something like that. Seem pretty tuff to me.