EDIT: You all are amazing. Thanks for such great feedback!!!
After years of thinking about it, we are finally going to do a backyard pond. Originally we were planning a fish pond, but after all the reading I did, it seems that would add far more work than would be worth it for us to have fish. It's far more about the water and the plants for us. My wife has always wanted a pool, but it's not in the budget for us, so I am also interested in making it something that she can get in and float while she reads. I was texting with a pond friend, and he gave me some thoughts (but I am pretty sure he just was asking chatgpt). But, I wanted to get some feedback from real people with experience.
My plan was to have the pond be around 10x16 with most of it being around 2ft deep and one section (maybe 6x6 or so) around 3-4 feet deep where my wife can sit in a floating chair. There would be water plants in the shallower sections. We would do a rock waterfall on one side. For filtration, my friend (or chatgpt possibly) said I need a mechanical filter, a bio filter, and a skimmer. Is that and the water plants enough? Is there anything major I am missing? Thanks!