Legal Question in Landlord & Tenant Law in California

Re: holding rent payment

Under California law you are allowed after giving reasonable notice to the landlord or his/her agent to repair damage to your unit not caused by you and to withhold up to one month's rent actually spent to fix those damages. You can not just withhold the money and not spend it for repairs.

You should again try to contact the landlord and tell them someone must come immeditely to take care of the mold problems as if it is not remedied yo might have to move out for your own health [it would be a constructive eviction so you do not have to give thirty days notice]. It is best, however, to try to be diplomatic with the landlord so as not to cause you troubles in the future.