Rob, it wasn't me. Essentially a diver goes down and looks (feels) for current. A strong light might help. In cold water he would have to be tougher than me. Unless he has a dry suit. Those things are cumbersome. Something this big should be pretty easy to find. The problem is that it could be one hole or a long skinny crack. The rope would be for use if it is a sucking hole instead of a crack. I don't know what you could do about it without a lot of expense. Going down and finding a problem is one thing. Underwater repair work could get really pricey.

It's not about the fish. It's about the pond. Take care of the pond and the fish will be fine. PB subscriber since before it was in color.

Without a sense of urgency, Nothing ever gets done.

Boy, if I say "sic em", you'd better look for something to bite. Sam Shelley Rancher and Farmer Muleshoe Texas 1892-1985 RIP Grandpa