Do you get any support from UC? They could pay up for 85% of the nursery fees. I’d always talk to your ex about paying more
What custody arrangement do you have? Easy if you have joint, pay and send them to nursery for the days you have the baby and let him sort out the other days.
My ex pays a lot more in child support, and he still paid the majority of nursery fees. I had to break it down for him and let him know what I spent on our son on the average month and also he's a higher earner than me and I've gone part time to look after my son more. I'd have a talk because what he's paying does not cover much.