Toilet leaking from tank to bowl

Toilet Leaking From Tank to Bowl | Troubleshooting and How to Fix It

How to install a toilet flange

When considering the plumbing environment in your house. The toilet is the most important area that should be in tip top condition. The reason for this is because the toilet is the place that deals with tons of water that has to be used on a daily basis.

And your bathroom that’s combined with the toilet is being used over and over again.  Every member in your house, even more than the kitchen or pantry. So, it’s important not to have a toilet leaking from tank to bowl in your bathroom on top of everything else.

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With our busy schedules, even If you are experiencing a heavy water leak from your toilet tank right now. Due to the fact that it’s leaking right into the bow without making a mess. It may not stress you out too much like in a situation where you are experiencing a plumbing issue. It affects your day-to-day activities such as dealing with a leaking pipe or a clogged toilet.

Where your whole lifestyle gets affected badly. But, if you are dealing with a toilet leaking from tank to bowl, you are mainly worried about the frustration you have to undergo after reading the huge water bill after a month or so.

It’s great if you can hear or see the toilet leaking, but what if it’s silent?

The indications of such a water leak could be diagnosed easily if you can observe your toilet bowl carefully while the toilet tank is full. This is the easiest way to find water trickling down from your tank into the bowl. The other way of finding out water leaks in your toilet tank is constantly or periodically hearing the “shhhhhh”. Such sound even though the toilet is not being used by anyone at the time.

It’s pretty straight forward if you can hear or see the toilet leaking from tank to bowl for yourself. But what are you going to do if this leak cannot be heard or seen by a human, acting as a silent killer of your wallet. This is actually a minor hassle that can be solved easily using just a little bit of spare time and patience only. So, let’s take a look at two simple experiments we can do quite easily without much effort.

A better way of checking water level in the morning

The first test is the easiest to perform, and this one isn’t any sort of rocket science with plumbing jargon. The only thing when performing this test is that you’ll have to wait till night time to do this successfully. All you got to do is, once you have finished all your night time toilet duties of poo and pee.

Just open up the lid of the toilet tank and wait till the tank is full after the final flush. Now you can mark the level roughly if you want. Just make sure that the tank cannot be filled with any more water at this point. Now cut off the water supply into the toilet tank and go to bed.

After you wake up in the morning you can check the water level of the toilet tank. If the level of water is at the same level as it was before you went to bed. Then that means your toilet tank is not leaking into the bowl.

But if you feel that the water level has gone down below the level you have marked.  It means you have a situation of a toilet leaking from tank to bowl.

You can also try the all popular colorful test

Before we begin, it’s important to have clear water in both the toilet bowl and the toilet tank because, we will be adding some color into the toilet tank in the form of dye. You can get dye tablets from a hardware store or a plumbing supplier. If not it’ll only cost you pennies therefore you don’t have to worry about the cost. If all these are checked, let’s do our test without wasting more time because if your water is leaking your money is too.

Remove the lid of the toilet tank and drop a tablet or two of dye right into the tank and wait till it turns into a dark color. You can either close the lid or keep it open. Just leave it there for about two to three hours or if you are really concerned, you can keep it overnight like what we did in our previous checkup.


Toilet leaking from tank to bowl

Now you can check the color of the water that’s in your bowl. If the color is crystal clear, then that means the water that was dyed in your tank has not leaked into the bowl. But if the water in your bowl has turned into the color of the water that is in your tank or even if it has turned into a lighter shade of the dye, that means you have a toilet tank that’s leaking water into the bowl for sure and you do not have to perform any more tests to confirm it.

What could be the cause of a toilet leaking from tank to bowl?

Well, there could be many reasons for this to happen. Therefore we cannot pinpoint one particular reason without physically investigating your toilet. A common reason for this to happen is because the fill valve or the ball valve is being set too high. Making the water in your toilet tank overflow into the overflow tube. If this happens, this overflow of water will definitely trickle down into your toilet bowl.

Other reasons are damages in the overflow tube itself. A worn-out flapper that can result in a malfunction in the flushing mechanism, worn out gasket. It could be due to the overuse of the fill valve or the ball valve.

All of these reasons mentioned above will happen eventually, after years and years of usage. And we have to understand that it’s not abnormal for a toilet to have such wear and tear over time.

Remember: When reattaching the tank to the bowl, just remember not to over tighten the bolts that secure the tank to the toilet base or you can easily crack the tank.

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