Bactoplus Fresh PSB is produced fresh and to the highest standards in the Netherlands. Fresh PSB consists of live Photo Synthetic Bacteria which are are able to digest large amounts of organic material and thus directly improve the water quality of your pond, ensuring healthier water and a better living environment for your koi and pond fish. Fresh PSB is active immediately after being added to your pond and sets about improving the water quality and clarity by removing ammonia and other impurities from the pond. Bactoplus Fresh PSB bacteria do not consume any oxygen, so they can be used at very high dosage levels for maximum effect. Bactoplus Fresh PSB Food Spray is also available for spraying onto fish food to stimulate improved colour, growth and health of your koi and other pond fish. Dosage:Use Bactoplus Fresh PSB at a water temperature above 12°C. For initial use in new ponds, add at least 10ml per 1000 litres of pond water for 5 days (2Ltr = 5 x 40,000 litres). For initial use in existing (polluted) ponds, add at least 10ml per 250 litres of pond water for 5 days (2Ltr = 5 x 10,000 litres). For maintenance dosing, add at least 10ml per 250-500 litres of pond water every week, depending on the number and size of the fish. Fresh PSB goes to work immediately. The higher the dose, the better the effect (overdosing is not possible). Switch off UV equipment and ozone generators for at least 24 hours after adding PSB. Shake well before use. Store in a frost-free, well-lit location to keep the bacteria alive.