Month to Month additional rent

[Shelly Irwin]

The lease I use for my rentals states that after the term ends that the lease converts to a month to month and that the rent is $25 more a month unless a new lease is signed. If I did not enforce by notifying tenant immediately, can this amount be withheld from their security deposit? Was I required to notify them that they were not sending additional rent? They have gotten real pissy and are moving out and I want to know if I can claim this additional rent for the past 8 months since they are not giving me the proper 30 day notice which is required.