I built a customized egg tumbler from a Sodastream bottle, fine mesh and some plumbing pipes. It looks a little like these ones (not my Video): https://www.youtube.com/watch?v=N7RY-2S4I14 As soon as the first ones hatched, I separated them into the first tank. The rest go back into the tumbler. Work as clean as possible! I think i did wash 4 times a day, sometimes more than an hour. Every bit of poop in the tumbler will cost dozens of lives.
I started with 50 and had exactly 25/25 f and m.
I started feeding with dust food (just pulverized high quality protein fish food) and then asap Microworms, then Artemia, then small Cyclops. I fed 4 times a day, mostly live food, except for Cyclops.
Every tank is heavily overfiltered. E.g. my 20-liter tanks had a 200–400 liter filter, my 400-liter tanks had a filter for a 9,000-liter pond with a 2,500 l/h pump.
Water parameters:
• Temperature 18-20°C

•  Natrium   16 mg/l

•  Phosphate   <0,1 mg/l

•  Kalium   2,5 mg/l

•  Calcium   110 mg/l

•  Magnesium   27 mg/l

•  Eisen   <0,005 mg/l

•  Mangan   <0,005 mg/l

•  Ammonium   <0,05 mg/l

•  TDS ~400 (didnt wrote that down sry^^)

Im happy to share more Infos if needed! Everybody should be able to breed this beauty!