Lee Calladine's video: Everything you should know about UVs

Green water and UVs clarifiers. What do they do? Hi its Lee from the Japanese Water gardens. In this video I am going to be explaining everything you should now about UV clarifiers. What are they, what do they do, do they need maintenance. Let me answer these questions and expose a few myths about UVs. Back in the early days of pond keeping some clever sole not sure who that was made a fantastic discovery that changed ornamental ponds for ever. Ultraviolet Light is damaging to single celled “green algae” - a common cause of murky water in ponds. Zap the algae with powerful UV rays and irreparable damage is inflicted onto the DNA. Yes exactly the same process that can cause skin cancer and makes you look like a prune by the time your 50. Once the DNA of the algae is damaged it tends to form heavy clumps that, sink to the bottom of the pond or get trapped in the filter media and then die. So long as you're killing off the algae faster than it is multiplying the water becomes crystal clear and you can see your lovely fish. UV are rated in watts. Watts are a measure electrical power consumption As a general rule of thumb I would suggest that you allow at least 10 watts of power for every 1,000 gallons or 5,000 litres of water in your pond. In my experience there isn’t much to choose between UV brands. You can spend hundreds of pounds of your hard earned money on a shinny looking stainless steel UV but, I am skeptical about any benefits there are to be had from such unit. Try to buy a unit that uses standard non-proprietary generic spares as they will save you a lot of money. Most UVs will come supplied with universal hose tails to enable easy installation onto flexible hose. To connect to a solvent weld pipe system you will probably need to purchase a pair of suitable in expensive adapters. It does not make much difference where the UV is installed it can go before or after the filter it will work equally well. Does the flow rate make much difference? I don’t believe that it does but you certainly should not be running a hugely powerful pump through a tiny UV as this could restrict your flow or even blow the rubber seals and cause a leak. Along with your bio filter the UV will need to be powered up and running 24hrs a day but it should not be in operation at any time your pump is off. Otherwise the lamp can get hot and scorch the inside of quartz sleeve. After about 6 months of operation the lamp will need to be replaced. Even though the lamp may appear to be illuminating the visible purple light is not UV light. When you service your unit take care not to damage the delicate quartz sleeves and don’t expose your eyes to the lamp as it can be harmful. UV lights have no effect on blanket weed, the stringy algae that grows of the side of the pond. To eradicate blanket weed you will need to use a separate treatment such as Cloverleaf Blanket Answer. Check out my best blanket weed treatment for more information on that amazing product. Sometimes UVs are described as sterilizers, suggesting that they will eliminate parasites and bacteria, whilst it is true to say that UV light is harmful to parasites and bacteria the power output from a domestic unit will be nowhere near sufficient to have any appreciable benefit. It is a common practice to turn off the UV during a pond treatment, whilst establishing a new filter or adding when adding living bacteria. Do you really need to do this? Maybe may be maybe not. The UV by itself does not guarantee clear water, to achieve this you will still need and efficient mechanical filter, but there is absolutely no doubt that a UV light is an extremely useful piece of equipment that every Koi pond should have, without a UV maintaining clear water is all but impossible. I hope you found this video of interest, if you would like to see please subscribe to the channel click that bell think and leave any questions in the comments below. Its bye for now from Lee and the Japanese Water Gardens.