What to do with he fries?

Hello Neki,
You really do need to keep your water scrupulously clean for fry - especially South American Cichlid fry (Angels and Discus particularly), they are just so incapable of coping with ammonia and nitrites, but especially ammonia, even though the adults can (to a larger extent).
You can, of course, try removing the eggs/larvae (wrigglers) and have a go at raising them artificially but even so, cleanliness is of the greatest importance.
Liquifry is a good starter food as long as you do not overfeed it, it quickly starts to decompose and really water needs changing a while after you have fed with it.
Far better starter food for Angel Fry is newly-hatched Brineshrimp, (see Puddlefish's excellent article in 'Foods and Feeding' section) but any uneaten shrimps will die and so will need to be removed too.
No food should be offered to the fry until they are fully free-swimming.
But, to do this (raise artificially) is to lose the huge pleasure you get from watching the parents herding their fry around, graciously gathering up any which stray too far from the 'pack'.

My advice would be to leave them with the adults until the parents change their parental role into one of wanting to breed again, then take them or the fry out promptly.

I would not advocate a breeding net for fry with Angels or most other Cichlids in the tank as they have an unpleasant habit of trying to 'suck' the fry through the mesh, which obviously they cannot achieve, but the fry die all the same.
Those are my views, but others will possibly differ, that's what is so good about this sort of Forum, it's a stage for everyone to air their views and opinions

John