Water level in bowl dropping

2 months ago I installed a Toto Drake toilet and it worked fine.

However, just lately, I have noticed that after the bowl fills with fresh water it will drop down about 1/2 inch within 5 minutes. After that it seems to stay at this new level or if it is dropping further it is unnoticeable.

Other post seem to believe this is a symptom of a small internal crack in the toilet itself.

I think what is confusing me is that there was no indication of this type of problem during the first 2 month. I can't imagine what would have changed things. I am the only one using the toilet and there are no kids around the house to clog it up. Also no evidence of leaks around the bowl or downstairs in the basement. And I've been using the toilet just as it was intended.

Anyone have any other ideas as to what I can look for?

Thanks. Jim

Two small dogs that can see over this ADA sized toilet. If only the explanation was that simple!

has it been very windy outside while this has been going on? when we get a big wind storm around here the wind will blow down the vent stack and suck the water out of the toilet bowls in our house and this could be what your experiencing.

It was very windy recently, so your suggestion does make sense. But today is not near as windy and it still drops that 1/2 inch about 5 minutes after refilling.

Surprisingly, it seems to settle down after that initial 1/2 inch.

But I will keep the wind idea in my memory banks and verify on a non-windy day. Thanks for the suggestion.

Jim

If there's something caught in the trapway, it can act like a wick and draw water out of the bowl. Nearly all toilet bowls are overfilled during refill, but it doesn't take all that long for the level to stabilize at the end. Wind can cause the water to rock back and forth and since some can go over the lip, it's lost. Flow in the drain can cause the same issue if the vent is partially blocked - changes in pressure in the drain system for the same reason as wind.