50/50 custody and expenses

on med stuff, co pays hardly comparable to monthly health insurance premium for a family. Sounds like you need mediator not court if all even.  If you don't have a written agreement you are going to be squabbling like this until the kids are out of college.  If you make more than him, going to court may end up with you owing him child support. You might get your co pay back less 50% but may have to start paying for monthly premium for kids at 50% in additioon to 50% on copay.

My ex took me to court to make me pay her bills even though I was paying her more in child support than ordered, she ended up with 1000 less per month. So do the math first.

you have two choices - take him back to family court to make the parenting plan/custody order more specific as to who is responsible for what - or what the split will be if applicable as well as reimbursement for what you paid.

OR

sue him in small claims court for what you feel you are due.

We are divorced as of Sept 2009,  we have a 50/50 custody order, no support. Kids alternative every other week.    This month i have had them more, but usually it is 50/50.  
Our incomes are about dead even. i received a bonus each year which puts me as making more, but this year with down turn i will take an income hit.  

oops typos sorry - it sent before I finished....

"anything filed"

also -

does he give you any child support?

you don't have any information in your profile to know where you are in the divorce process - do you have anyhting fied inthe courts yet at all - or do you live apart but not legaly separated?

What you can or should do depends on this information. Also, how much time are the kids with you vs him?