Los Angeles water bill

[Jerry Akop]

I have a 4 unit in Los Angeles, rent control building. I lay the water bill. Usually $400-$500 every 2 months. My last bill was $1500. I notices one of the unit bathrooms was running water. I adjusted and the meter stoped. But i feel like somehow they are still running something. Prob on purpose. Can i split the bill between the tenants being a rent control building? I checked middle of the night and the meter was running. Please help. Thank you.