Golden Rule Lease Clause?

[Kelly N.]

Hi BP,

We have been leasing apartments in our multi family units for a while now, but have never before seen the possible need to include a lease clause with the Golden Rule in it- treat others as you wish to be treated.  We have a clause about "use and quiet enjoyment" and one explaining that the tenant is responsible for damages done by themselves and their guests, but nothing covering how tenants and their guests should treat others in the building. 

I had one tenant put up a note asking if the other residents could either take out their trash weekly (as required by the lease) or if they would like to contact her about working together to get it down- she takes out the trash and the other residents return the cans to the house.  The notice stayed up for a week, then today she sent me a picture of the note with what had been added to it by other residents or their guests the night before- some unintelligible gibberish but also a "F___ U!"  Since this treatment of others isn't covered by my lease, the tenants of all 3 apartments have been informed that I will be adding a clause to the lease concerning treatment of others- our lease does say we can make new rules as long as they are reasonable and in writing. 

Any ideas on what the wording should be?  What other actions should I take at this point? 

Thanks in advance,

Kelly