When I use a cup/container to artificial hatch-I lower the cup next to the nest and allow it to flow in the cup-Anchor, nest and eggs all flow into the cup. Very few of my eggs fall-but the ones that do fall to the bottom usually will hatch-I like to add a very small common snail after the first 24-32 hours more or less. The snail will eat the bad eggs first before they start on the healthy eggs and this helps to keep all of them safe IME.
Some males are picky and some could care less if you watch them spawning. Usually what will cause a male to eat healthy/fertile eggs is when they are disturbed too much-like, when you put your hands, nets...etc.. in the tank or move things around too much etc.....
Some males will feel threatened and eat the eggs/fry-They look at it like if anything is going to get that high protein..I will-so that I will have the energy to spawn again.
Some males could care less what you do in the tank-I have some that I can move the male out and then add him back and he still tends to his offspring and others if you do anything near the tank they eat eggs and/or fry.
They do love to keep us on our toes....lol.....