When I split from my xh (5 1/2 years ago) he became very unreliable at paying so I got the CSA involved and when he eventually sobered up he set upa astanding order to pay the amount they recommended (£14 a week for 2 kids).Since then we have never changed the amount although he does contribute towards clubs etc(as in I pay then he gives me £20 for a couple of weeks).
I have used the CSA calculator and worked out they now recommend £42 a week.
As its such a difference am quite temped to broach the subject but he is so tempramental it will prob end in lots of argument/stress.
Would you bother?