CSA - Should he claim it

My BF has successfully claimed CB for one of his three children reflecting the amount of time the children share between homes. This now entitles him to claim Tax credits for one child also. So far through this divorce my BF has been stripped financial (escalating court costs now in excess of £20k, diminishing work through child commitments and credit crunch) and is barely hanging on by his fingertips. He spends approx £30 each week on shopping for the time the kids are with him (to make sure they have everything they need) and when hes on his own he survives mainly on cereal and fish finger sandwiches, if I dont feed him he doesnt have a proper meal when he doesnt have the kids.

The dilemma is he is now entitled to claim CSA for the one child he claims CB for from his ex wife (she left him for another man - family friend). This would give him slightly more income and reduce his current CSA payments enabling him to be a little bit more financially stable and not fall so far below the breadline, although he would still be below an acceptable level of income to maintain himself and three kids half the week. It is a terribly acrimonious divorce and he really has had a tough time (as I am sure many of you have) this money would be used solely for the children. Should he or should he not claim what he is entitled to?

Any advice is appreciated bearing in mind my BF can do nothing right by his ex anyway and there will always be something to fight about, if its not one thing it will be another.

I think you said it all and answered your own question.

He can do nothing right by his ex...

Get what your entitled to, well done him.

I am sure that he is able to claim CSA if he is in receipt of child benefit. What is the division of time the children spend with him?