My 50% wilds (blue rams) would spawn every 5-7 days in water that had a pH of 7.8-8.0 and a GH
of 300+ ppm
with tons of iron. They would lay large clutches with over 400 eggs each time and I'd get over 95% fertility each time.
Survival rates of ram fry are dependent upon water changes mainly. The water should be changed out 2 times per day if possible, once at the least until they are ~3/8" or so.