The past couple days it has been over 109 degrees. With water evaporating from the pond I added more today. I keep the level of water in the pond as high as I can so the fish can stay cooler. The lillies need time to grow and cover the pond area providing shade to Goldfish/Koi, I use the name Koi lightly as these are not authentic Japanese Koi.
After adding the tap water I immediately put in a Stress Coat. My current brand is by PondCare. After a day I put in my weekly treatment of ECOFIX, also by Pond Care. BE SURE TO FOLLOW DIRECTIONS COMPLETELY! Your pond needs a good filter system especially when adding these chemicals.
Filter after Filter, finally I believe I have discovered the TOP, The BEST Pond Filter System – LIFEGARD All In One !!! Look in the right hand photo, you can see it. It cost a little more but it is so worth it! The comparison to my other filters is “this one blows the others OUT OF THE WATER.”

