I'm no professional, barely even know how to spell it, but I would think you may be over thinking the testing thing, while the pond is filling up and settling out, along with a little erosion and settlings from the construction part, your numbers, I would think, are gonna vary a good bit, but almost worst case scenario they are probably not going to be off so far as to have any kind of attrition of fish.
Once it fills up and levels off, and settles out, and the summer sun hits it for a while, then do some testing as to water quality and such and make some adjustments if needed. jmo
There's a thousand, 30 yr old ponds out there, with some pretty great fishing in them that have never had a water sample in their entire existence.
Good Luck tho and enjoy your new fishing hole!
