It's completely above ground. It's 22" deep
Here's some photo's of it going together:
You are correct- we don't have any filtration system-only the pump and fountain. We dealt solely with a business that has been in the pond business for 12 years. They have several ponds-both above and below ground, many with koi and they do not use any filtration system. They told me that if I am patient, with the right number of plants and not too many fish the pond will take car of itself. Our water went murky about 2 weeks after it was built, then as the plants started to spread the water cleared up- almost overnight. It was amazing to see this happen. I did have to treat stringy algea using a product called "pond balance" and I have added fertilizer for my suffering water hyacinths. I think next year we'll build up one end (the end closet to the house) and add one of those filter/waterfall units. I do have to clean the pump inlet every 10 days or so. I also just got one of those water vacuum tools to clean silt from the bottom. The view with my underwater camera is very clear- about 4-5 feet however some of the fish like to stir up the silt on the bottom.
Todd