Leaky pool repair anyone use eBay hydrophone to find leak

[Delmar]

We have a leak that is hard to find. We saw a guy on ebay that sells a hydrophone for just a few dollars. Has anyone used a DIY hydrophone to find a leak by themselves or do you think it will be a waste of time?
Is there a better way to find leaks that does not cost a lot we can do ourselves?

[PoolDoc]

I have always found leak detection to be hard and time consuming.

As a rule, it's easy to find leaks, but often hard to find "the leak". I got to the point where I would tell customers that I had found "some" leaks, but not "the leak".

If you want to post a URL, I'll take a look, but for a few dollars on Ebay you may be buying something like a cheap mechanic's stethoscope.

Regarding hydrophones, I've never used them. But those I've talked to who have have told me it takes experience to use them effectively.