Oh, oh, mine kick out the eggs with every batch (now the 11th batch) and highest hatching no. is 90+. I am now more familiar with artificial hatching. I never had once that daddy does the job.
1) fill a tub with new treated water.
2) take eggs out and drop into the tub, add strong aeration.
3) add methylene blue, how much will depend on the size of the tub. I usually add 2 drops in a biscuit container
4) On day 3, pour away water containing MB, add new treated water
5) From day 3 onwards, start observing the clutch of egg for bad eggs. If possible remove them, if they stick too tightly, then imitate the fanning process by blowing at the eggs with a pipette regularly.
6) Day 4, most eggs would turn very orangy, try blowing hard at the clutch to try to blow out the good orangy egg and away from the clutch. But if there are no bad eggs amongst the clutch, then no worry, no need to do that.
7) Day 5, wrigglers will be free.
Can add a matured bio sponge (optional), then DO NOT WC until the egg sac are used up, ie. for the next 5 days.
9) Day 11, move these fry to fry saver.