Plants and Parasites One of the most frustrating things that can happen to a pond owner is just to start to lose fish, just when your everything is finally going great. I've seen it many times, and also had it happen to me. You spend all season planting, feeding, and caring for your pond and then all of a sudden, your fish mysteriously start dying off. For many people, the cause will always be a mystery.  Your water levels test fine, you haven't added any new fish lately, and there are no outward signs of stress or infection. So what's the likely culprit? Not all pond owners know this, but you can just as easily introduce unwanted bacteria and parasites into your pond by adding new plants, and when adding new fish.  Think about it, the plants usually come from rivers and streams from all over the place, and are then placed in holding tanks at the plant distributor's location for resale.  And often, they are placed in the same water that is circulating through any fish holding tanks they may have, for the fish they sell. So, there are two potential places for the plants to pick up water born bacteria and parasites, and since the plants are shipped wet to keep them alive, these parasites and bacteria will also make the journey. By adding new plants into your pond without treating them for parasites, is just like adding the new fish you just bought down at the local pet mart, without quarantining him. How do you treat the plants? One way is to dip them in a mixture of heavily salted water for 5 minutes.  The difference in salinity will often kill any parasites and bacteria on the plants.  This is by far the easiest way. Another way is to soak them in a mixture of water and Potassium Permangenate for 5-10 minutes.  This is harder to find, but is valuable to have on hand for this, especially if you are having trouble with parasites every year. By taking this precaution, you will be ensuring that your goldfish and KOI are protected against the majority of parasites that could come into your pond this way. More Articles