Why a leaking toilet needs prompt repair
Yes, usually. A toilet that constantly runs, leaks, or will not flush properly is generally the landlord's responsibility to repair, as part of keeping the plumbing in working order.
A running toilet wastes water and can drive up a water bill, while a leaking toilet can damage the floor and the subfloor beneath it and lead to mold. Both are plumbing problems the landlord is expected to fix — not something a tenant should have to live with or repair on their own.
If a leaking toilet is causing water to pool or seep, report it promptly, because hidden water damage under and around a toilet can spread before you notice it. Keep your written report and dated photos. If your landlord ignores a running or leaking toilet, a free review can help you understand what they are required to do.
This is general information about California tenant rights, not legal advice. Every situation is different.