I started using Bank Rec mid March, before that i did my bank rec in AP. I tried reconcilling March but i can't seem to make it balance

You didn't ask a question.

You didn't actually do your bank rec in AP. Maybe you used AP to generate a list of outstanding checks, but that is not the same as a bank rec.

Steve

When you start using Bank Rec, you have to enter a reconciling transaction to account for the prior balance in the bank. Do not post this transaction in GL.

Perhaps the reconciling transaction is missing.