Question Details:He paid a security deposit but not last months rent. Can I now give him a 72 hour notice for non-payment of rent and would it supersede the first notice?
When you served the tenant with a 30-day notice, he/she was given a certain amount of time to pay the rent that is owed. If the tenant failed to do so within the legal time given under the notice, your legal recourse is to file an eviction action in court. You cannot now suddenly decide that you want to give the tenant less time to pay the rent than he/she is entitled to under the first 30-day notice. You could have served the tenant with a 3-day notice but chose a 30-day notice instead. You can't have it both ways. Imagine being served with various notices that give you different amounts of time to pay the rent.
Your next legal option is to file an eviction suit in court if the tenant does not pay whatever rent is owed. Trying to give another notice that gives the tenant less time to comply sets you up for being possibly counter-sued by the tenant for improper notice. This can also delay your eviction suit and result in the tenant remaining in your property longer without paying rent. That's not the outcome you want.
You may want to consider speaking to an attorney to help you with this.