This is a picture of how the office pond looks now, with 15 Koi and 2 feeders that made it through a lengthy nitrification process. Initially set-up in September with a Fluval 400, the filter was upgraded in October after additional Koi were added. Unfortunately, the pond inhabitants suffered a great deal during the nitrification cycle and the initial 13 fingerlings, one Platinum Ogon, and a 6-inch Gin Rin Yamabuke Ogon were lost. At that point, a 95% water change was conducted and the filter was cleaned. I added 30 feeders for about 2 weeks while the pond completed its cycle. 15 3-inch koi were acclimated about a month ago and the water quality tests perfect every day. These fish eat well, 2-4 times each day and are thriving.