Signed a lease for 18 months which states that when lease ends it will go month to month with thirty days notice. When lease ended we did not sign new lease landlord said he would like to keep it month to month. We gave 30 days notice but he said we were to give 60 days instead. Florida statue says different. House was leased by a company I worked for but I was terminated 3 days after signed lease ended.

This is all I could find
Florida Landlord Network - Renter Rights Handbook

Ending the Lease
There are two different kinds of tenancies, tenancies of specific and of nonspecific duration.

Tenancy of Nonspecific Duration:
A tenancy of nonspecific duration may be either written or oral. Either you or your landlord can terminate such an arrangement upon the following notices: (F.S. 83.57)

Either party must provide notice at least this far in advance of the next rent payment date in order to terminate the lease. This means that with a month to month lease, if either party wants to end the lease October 1st, they must notify the other party on or before September 15th. If one party gives notice on September 17th, that party cannot end the lease, without the other party's agreement, before November 1st.

If you give this notice by personal delivery or certified mail, then it will also satisfy the notice requirement for getting your security deposit back. (see Chapter 3) Be certain to include your forwarding address.

Since your month to month states 30 days then it should be 30 days

If your specific lease says, that it will go to month to month with 30 day notice then that is your written rental agreement.

When a written lease ends and the tenant stays on a month-to-month basis, all terms of the prior written lease are still in effect (except for the term). If the written lease stated that the tenant needed to give 60 days notice that they did not intend to renew, then that provision still applies.

What did your lease say?

I side with Lisa. If the lease specified 60 days notice, then it remains 60 days. However, if the lease states that after the 18 months it goes month to month with 30 days notice then that provision of the lease applies.