Using the hooze with jet noozle….

Step 1 of pond leak identification just completed ….refill pond (didn’t expect mini-Nessie to rise!)
Tomorrow….
Step 2 use some fluorescein dye I happened to have handy to see if I can see where leak is…other ocular methods having failed miserably! 
Step 3 apply some dark waterproof tape.

Other suggestions very welcome, but why not entertain yourself with the source of my subject heading first? :-))