Add as much air to your pond as you can using air pumps and air stones to distribute the air (highly recommended for ponds that are heavily stocked). You can add the air directly to the pond, the filter, the waterfall and anywhere else you can think of.
TetraPond Pond Fish TreatmentPond Fish Treatment helps to protect goldfish and Koi against infection by destroying harmful parasites, bacteria and fungus. Pond Fish Treatment also helps to prevent Ich.
Tetra Pond Koi Vital
Improve the vitality of your Koi
Specially formulated water conditioner for Koi which contains essential trace elements and vitamins, improves vitality, stimulates breeding and recreates their natural water conditions.