Virkon S Aquatic (50 x 5g) Low Foam Tablets

Awesome

Speedy delivery and works as descibed

I've kept Koi for over 20 years. This is perfect if you want to disinfect your pond of bad bacteria, viruses and fungi. A big positive is that it has little or no impact on biological filtration. Easy to dissolve in a watering can of pond water, and just distribute over the pond surface. No need to turn off UV, but remove any carbon from your filters. Just add 5g per 1000 gallons, every week for 3 weeks. You can safely use double this on the first dose. Any knocks my fish had soon healed without any secondary infection. Great stuff :)