I saw this a while back, 6

9 as 6 appears to be sealed. Really need a better plumber to sort this out.

The answer is 9 because you're not supposed to ignore the errors

3!!! Are we debating for fun??? Let’s do it!!! OK I’m going w 9 actually. The welder was highly regarded.

9 😎

If the pressure is low enough that the water can flow without overflowing the initial drop, then three will fill and then overflow indefinitely and that's it. But if the pressure is higher, that changes it.