I am new to this forum and new to pond ownership as we purchased a house last year in Southern Arizona with a 1/4 acre pond about 4' deep that was stocked with bass and mosquito minnows. There was a resident duck (Daffy) who found a mate last fall and flew away with her
(at least there was no sign that predators had gotten them both).
Last summer during monsoon season, we had a flood during a heavy rain in which water from the cattle ranch to the north flooded the pond and left manure stink, some dead fish, and stimulated a lot of underwater plant growth (duckweed). We manually cleaned, added lots of fresh water, and our aeration pump sits on the bottom, pumps the water out a little rivulet up a slight hill to a creek bed that then flows down to the pond, over a water fall. It brings in oxygen but doesn't get the water in the entire pond moving.
The pond developed an algae problem quite recently this year and we have been removing manually. The muck is not too deep, maybe 3" or a little more in the center. In searching for solutions to restore the health of the pond, I have been reading on this site but, as always, there are different opinions and different products. Since our cats drink out of the pond and the creek, and lots of wildlife come by to drink here in the desert, and some people swim in the pond, we only want to consider remedies that are  non toxic and  can establish a healthy biome that maintains itself with minimal intervention.
Solution A most recommended on this forum seems to be purchasing big tilapia that won'5 become snacks for the bass. If we go this route, how do we figure out the size when our bass range greatly in size? Also, how about numbers? And finally, will we have to eat the tilapia to keep their numbers in balance with the bass, which we do eat?
Solution B we found on a commercial site. It involves purchasing four products that included healthy bacteria and enzymes. The pond is surrounded by mesquite trees, one mulberry, and a butterfly bush, so it's in partial shade most days. It also has about 1/10 of the surface covered by lily pads that produce yellow flowers. The mesquites drop small leaves and flowers onto the surface. The proposed products were supposed to deal with the muck, the algae, and digesting the organic matter. I'd like to hear from anyone who has used this kind of approach with success. I don't mind a one time expense but won't get into a yearly have-to-repurchase to keep it going.
Solution C buy an additional pond aerator, ideally solar, to set in parts of the pond that the existing pump doesn't reach, and continue manually removing the algae.
BTW - we did borrow a backhoe, dug a huge trench near the properly line, and will not have flooding from the cattle ranch again.