I use marbles as substrate, and have heavily planted anacharis and hornwort in a cluster floating. Feed them brine shrimp or other protein like blood worms or daphnia but grind them up. I like using marbles because they’re easy to clean, look nice and hide the fry when they drop to the bottom when they’re born. They can also hide really well and sometimes you won’t see them until a water change or when they’re a week or so old. It also allows other fish to be in the tank and the plants help reduce fin nipping when the mother gives birth. Which means less stress. I keep all my dry in one tank as feeders for my turtles.
I learned these tricks from an old timer over 20 years ago, and this works better than buy all the useless supplies on the market.
When the mother is about to give birth she may hide, breath heavily, look like she has the shimmy’s (scratching herself on rocks). Her body will be boxed off, her gravid spot black. If she’s under stress, she will either abort or wait. If you see a fish bothering her remove it if you want the fry. I also add a little more water conditioner with stress reduction to help prepare for the fry. Do at least 25% water change a week, and turn the light off at night. Normally, I have fry the morning after a water change.
Hope this helped.