Oh Lordy, this pond. We moved into a new home last fall with a 2000+ gallon koi pond with 12-13 koi and goldfish (3 big koi and a bunch of smaller ones) that hadn't been properly maintained all summer, if not longer. I managed to get the pea soup decently clear by winter, but this summer has been very tough. I've been struggling with algae control since spring, despite seeding with bacteria. My pH has been testing high (over 9) both morning and afternoon, but all other levels (ammonia, nitrates & phosphate) have been 0 or close to it. I added 80 scoops of Microbe Lift pH buffer yesterday, and the pond is extremely cloudy (along with being green), and my phosphate level went from 0 on Friday to 10 today (Tuesday). I did drain approx 500 gallons and added in a little over 800, but I just checked the tap water and it registered 0 phosphates. Oh, and my pH is STILL over 9. My water hyacinths and lily pads are turning black on the edges and not looking good and now I'm afraid I've made it worse!! Tips? I built a quilt batting garbage can filter for algae control per the suggestions on other posts here, but haven't been able to run it a ton since we were away for most of the weekend. Oh, and I have another bottle of Microbe Lift PL that I was going to add once the pH was stabilized. Thanks in advance for any help!