| weewee, The show koi will be the first ones to die. If they are gasping at the surface, you have some serious stuff going on. You should concentrate on getting a massive water exchange and increased aeration. Before you can do a water exchange, you need to learn something about your source water (tap water, mains water). Is it chlorinated and what is the pH? If you have a pump, start pumping water into the air to splash and add oxygen. The fish could be on the surface because of gill damage or parasites, but the extra oxygen may buy a little time. Akai, 1 gallon = 3.785 liters 264.2 gallons = 1,000 liters = 1 metric ton steve hopkins |