Tenant overnight guest on rental Property

[Peng Thaung]

Hello,

I have a single family house in King county, Renton WA and currently rent it out as individual room per each single tenant. In my contract I set that each tenant is allowed three overnight stays per week for their guess for two weeks out of each month.  But seem like they have guess stay longer than what written in the contract, also there are some complain from other tenants in the house that say too many long stay guest in the house. 

My question are,

1. Does 6 days out of a month for guest to stay is reasonable period?

2, I'm thinking to reduce from 6 days to 3 days per month. Is that a good idea?

Thanks,

Peng