What's actually causing this
Toilets run when water continuously trickles from the tank into the bowl. The two most common culprits are a worn-out flapper that doesn't seal properly, and a fill valve that's stuck open or set too high.
What you'll need
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- Toilet flapper kit Shop →
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- Adjustable pliers Shop →
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Step-by-step fix
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1
Diagnose the problem
Lift the tank lid and add a few drops of food coloring. If color appears in the bowl within 10 minutes without flushing, the flapper is leaking.
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2
Turn off the water supply
Turn the shutoff valve behind the toilet clockwise. Flush once to empty the tank.
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3
Replace the flapper
Unhook the old flapper from the overflow tube pegs. Snap the new flapper in place and reconnect the chain — leave about half an inch of slack.
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4
Adjust the fill valve
If water is running over the overflow tube, the water level is too high. Adjust the float arm or float ball downward until the water sits 1 inch below the top of the overflow tube.
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5
Turn water back on and test
Slowly open the shutoff valve. Let the tank fill and listen for any continued running after the fill cycle completes.
In Las Vegas, tap water is very hard (360–500 ppm). Las Vegas has some of the hardest water in the U.S., sourced from Colorado River. Mineral deposits are extreme and visible within weeks. Water heaters fail very rapidly (5–7 years). Water softeners are nearly universal.
Plumbers in Las Vegas typically charge $100–160/hr. Most homeowners budget $800–2,500 for common repairs like fixture replacement, drain clearing, or valve repairs.
Nevada has minimal licensing for plumbers. Las Vegas requires permits. Homeowners can obtain permits and perform plumbing work.
Majority post-1990s construction. Copper and PEX standard. Extremely hard water causes severe sediment buildup. Water heaters fail within 5–7 years; flushing annually is essential. Slab-on-grade is common. Underground leaks are expensive.
DIY in Las Vegas: Las Vegas is extremely DIY-friendly. Nevada's permissive licensing, cheap permits, and strong DIY culture make it ideal for homeowner repairs. Very hard water management and HVAC maintenance are common DIY focuses. Water softener installation is often DIY.
- The tank or bowl has visible cracks.
- The toilet rocks or is loose at the base — this may indicate a wax ring failure.
- Water appears on the floor around the base after flushing.
Let Uncle AI diagnose it first.
Describe the problem. Uncle AI asks the right questions and tells you exactly what's broken — and whether you should fix it yourself or call someone in Las Vegas.
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