I'm James from South Mississippi. I just found this forum today. We installed a 500 gallon flexible liner pond in the fall and have two big goldfish. We have a small amount of pond plants shading the water and floating ( I wish I knew what the are) and some shade 50%? on the pond. Plus we have two store bought in-pond filters trying to keep up. I just started reading articles and I would like to investigate bio filters, water flow over rocks etc, anything to help clear the water. I can build stuff so it looks like fun. thanks James