Welcome to the Group!!! Always love seeing other's ponds, and OMG, you are soooo lucky to have found free rocks and have a choice of hundreds at that! I had to pay for most all of mine. My daughter did gather a bunch in UT, and brought them home with her last summer, but can't expect her to drive home with rocks each year. LOL Your plants and fish look super, too!
OK, there are a bunch of us "mature" women on here, and several of us, me included, dug our large ponds by hand, with a shovel! I will say, though, that the digging part was fund, easy digging, except the tree roots, which were up to 4" diameter, and the reason I was able to do this by hand is that I have a tractor with a loader that hauled the dirt away, or spread it accordingly. So, to me, digging was easy, hauling it away wheelbarrow by wheelbarrow was the tough part! Some people have really rocky soil or hard clay. I have more clay than rock, but caught the ground at perfect times both last year in May when I dug my 19x9x4D koi pond and this spring when I dug the 17x7x3D goldfish pond, which I added a 17'x3'x18"D bog on the back side of it! I loved the digging part as much as the end result. It was my therapy as well. The sense of accomplishment was tremendous! And, I think I got the initial pond dug in 10 days, probably 6 full days of digging, and 4 days of evenings after work! I love to work hard, and that was the ultimate job for me! I'd love to do this for a business, but at my age (54), that's not going to happen! And, if you wonder, I didn't use the tractor and loader because I was far too picky on how the sides were shaped.... or is it because I'm not that good of a digger on a tractor?! LOL