Al, very, very smart, from the leak detection contraption you built to your method of "noninvasive" patching. Brilliant, in fact, right down to using beet juice for the dye (and then eating them). Marvelous Al is what your name should be.

I'm not what you would call a technical-oriented person, and added to that I have problems with integrating spatial concepts. It would probably help if I knew what a "long thin piece of auto vacuum hose" is? But reading all this got me to thinking, stubborn brain notwithstanding.

I recently used my garden hose with a garden sprayer to spray a bleach solution while on my extension ladder to clean my lovely metal roof that acquires mold over the winter (this is, after all, Alabama). Why couldn't I use my garden hose with the garden sprayer (filled with beet juice instead of food coloring because I'm going to go through a lot of the stuff)? Turn the faucet on every so slightly, and slowly navigate it around the deep end? Your method, Al, is no doubt better because you have the rigid PVC pole, but I just can't understand how you got the dye to come out of the garden sprayer without it hooked up to some source that either pushed water through it or air. Wait! Perhaps a long thin piece of auto vacuum hose pushes air? If not, what mechanism pushes the dye out of the sprayer?

Canuck, I've been googling and the only leak detection device out there is an electronic one, and they're so expensive they don't even tell you the price! Again, I'm at a loss to understand your method. I have no clue what a "camera lens cleaner puffer" thing is and, just like my problem with visualizing a "long thin piece of auto vacuum hose," I get totally lost in the method after that.

I just printed off directions for a Bucket Test. While I'm pretty sure I have a leak, I'm not 100% sure. It seems the prudent thing to do. I hope this test can be trusted. Then, if I indeed have a leak, I'll first check the shallow end with my mask and snorkel. If it's in the deep end, then maybe I'll try the garden sprayer on the end of the garden hose method if ya'll think it would work, checking out the main drain, returns, and then seams. By the way, is the main drain at the bottom of the deep end what is used when you need to empty the pool to have a new liner installed? I can't think of any other thing it could be for. Otherwise, you'd use a sump pump and flood your neighbors out.

I sure appreciate you both sharing your ideas. Too bad we all don't live in the same neighborhood. We could have a leak detection party. And then eat beets afterwards.