Q. Our sublet was up five days ago. We put up with disgusting water leaking through the ceilings for the entire six months we were subletting. We won't sign a new lease until that is repaired. We signed an agreement with the original tenant, paid him a "move-in fee," and paid rent every month to the owner.

Last weekend while we were gone, out of nowhere, our 30-gallon aquarium decided to leak. It completely drained to the restaurant below. My theory is the banging on the roof from repairs cracked a seal.

We gave the landlord a rent check for this month before we were informed that both the restaurant and the landlord want to charge us. We don't feel responsible and sure don't want to pay the landlord because of the leaky roof. We are living here with no lease or verbal agreement. What we want to do is leave and stop payment on the check. I assume the restaurant will try to sue us regardless. How much can we be responsible for?

A. You ultimately may be financially responsible for all the building damage the aquarium leak caused. This could depend on whether the landlord's building insurance determines the leak was an unintentional accident, relieving you of responsibility under Illinois common law.

If money is owed, under a sublet, the original tenant could be the one financially responsible to the landlord. If true, he can legally turn to you for reimbursement. You are directly responsible to the restaurant for damages and lost business since it was your aquarium. If you had renter's insurance, it would take care of most of this. You may be able to offset what you might owe the landlord because of the lesser value of the unit and other damages caused by the roof leaks.

Blaming the aquarium failure on the landlord's roof work is far-fetched. Stopping payment on a check, except in cases of theft or fraud, has serious legal consequences. Talk to a lawyer before doing this.

Your status as a tenant is month-to-month, based on you offering rent for the month. To cancel a month-to-month rental agreement, you must give the landlord written notice at least 30 days before the end of the month you want to leave.

Write to Ed Sacks at Apartment Watch, Chicago Sun-Times, 350 N. Orleans, Chicago, IL 60654, or e-mail apartmentwatch@earthlink.net.