Adding an Ultra Violet Clarifier is a good idea if you have a significant amount of suspended algae in the pond. The UV light kills the algae and causes it to clump together. Once the algae is in clumps, it is easier for the filter to remove. Some UVCs can be submerged and some are only suitable for installation above ground. A UVC can be installed anywhere on the pressure side of the pump but the most suitable place is after the pump and before the filter. This way the filter can remove the algae. If the clumped algae is released back into the pond, it will settle out to the bottom.
To maintain peak efficiency, the UVC bulb should be replaced on a yearly basis even if it is not blown out. This is due to the fact that the UV bulb will burn less brightly over time.
Sizing the UVC is quite easy. All UVCs have a rating for the volume of water that they are recommended for and they all have a maximum flow rate. You can not exceed the maximum flow rate for the UVC. The suspended algae in the water needs to be exposed to the UV light for a sufficient period of time to cause the algae to clump together. If the flow rate is higher than recommended, the water will pass by the UV bulb too quickly for it to be effective. The higher flow rate could also damage the UVC unit. Other considerations are the flow rate requirements of the filter if you are powering the two items from one pump.
The UV Clarifiers do not include a pump. Now you have to find a pump or ensure that the pump you will be using is suitable. Calculate the total head to the position where the intake of the UVC will be located. Each type and size of UVC has a maximum flow rate listed for it. This is the maximum flow rate that you can supply the UVC with at the total head that you just calculated.
Now go to our main pumps page and select an appropriate pump that will deliver close to but not over the flow rate that the UVC you have chosen will require at your total head. The final selection is up to you. Criteria would be initial cost, power consumption, and manufacturer's warranty. The yearly operating cost comparison figures on the website make it easy to determine which pump will be most ecomomical to operate over the long term. Sometimes, a less expensive pump with a high power consumption will end up costing you more in the end.
For the purpose of operating a UVC, rather than using a pump with an integrated foam pre-filter, we recommend to use a pump that comes with a screen housing. The foam pre-filters clog up quite easily and require a lot of maintenance. On some pumps, like the Pondmaster Mag Drive, 250 GPH and larger models, the foam pre-filter can be replaced with a mesh filter screen.
The tubing size running from the pump to the UVC is determined by the maximum flow rate of the pump you select, as well as the intake and discharge fitting size of the UVC. Many UVCs feature step-down hose tails which allow attaching several different tubing diameters, for example from 3/4" to 1-1/2". These intake and discharge sizes are shown for each UVC. Recommended tubing sizes are listed for each pump that we sell. Pick the tubing diameter that is most appropriate for the pump and will fit on the UVC. If you can not find a listing for your pump, you can also use the tubing flow rate chart to determine the correct tubing (please remember to ensure that it will fit on the intake and discharge of the UVC). A hose adapter or a combination of adapters may be required to connect the hose to most pumps and you may require adapters for the intake and discharge fitting of the UVC as well.