I used an online pond calculator and yes its 35,000 gal, big enough to have an island that is about 10 feet wide. It has a large waterfall With about a 18-24 inch drop, I can't remember the gph of the pump, I also have a smaller pump running as well. It has prob 40-50 fish, large comments, large faintails, small koi, salamanders, and a couple frogs.
The small pond is probably around 1000, it has a small pump, but has a lot of plants that cover about 1/2 the waters surface, it has about 20 fish, med to large commets, salamanders, frogs, and a kazillion snails.
I do not test my water, have been very lucky with my fish, only had one problem several years ago and lost 5-6 fish, but I think I fed them bad food, discovered afterward that their bag of food had drawn damp and had mold in it.
Really wanting to get the water clear, but don't want a bunch of cost or maintenance, and worried about doing more harm than good.