Dr Pisky & the Green Death?

Ok, nothing so dramatic as that brilliant Dr Who series from the 70s, just me trying to locate the blasted pond leak. I happened to have a modicum of Fluorescein in my shed, so knew that would be a safe dye test, even if it’s a bit over the top. The local birdlife viewed it very cautiously, and some gave me what felt like comically quizzical looks!

Nowt conclusive yet, but   :-/