Rainbow Fish Courting Help

Boesmani (and most other) Rainbows will actually only lay their eggs a few at a time (I always find the optimum time to be when daylight first reaches the tank, but it will also happen when you first switch on the lights).
If you're able to, remove the bunch of plants - or at least as much as you're able to and carefully feel for eggs between your forefinger and thumb, they aren't too delicate and you can then remove each one into a container (I find the best compromise to be one of those netting 'breeding traps' which can now be bought in just about any Aquarium shop).
After you have removed the day's batch, replace the plant bunch and do the same thing the next day, and the next etc etc until you either have as many eggs as you want to deal with - or they stop laying.
Rainbow Fish eggs take a few weeks to hatch, but when they do, the fry are ready to eat straight away. But, there will be size discrepancies as - having been collected at different times - they hatch out pro rata and you could potentially reach a situation where the earlier hatchers have grown and will find the late lads to be ideal live foods.
So, if you don't want too many then only collect for a few days - if you do want more then a series of breeding traps is the logical way to go.
The best fry food - bar none - is newly-hatched brineshrimps.
They aren't the fastest of growers either, so be prepared for this - a 'grow-out' tank would be the way to go.
Of course, you could alternatively leave the eggs and fry to the mercies of both the parents - and the other tank inhabitants but don't expect too many survivors.
Hope this helps, if you have any further questions don't hesitate to ask.
John