UV Sterilization is one of the safest and most effective methods of preventing and eliminating problems in a pond. The UV unit consists of a plastic pipe with an ultraviolet lamp inside, and is connected to the return line after the filter. As pond water is circulated through the unit, it is irradiated by the UV lamp, killing free floating algae spores, bacteria, and parasites. UV radiation will not kill parasites on fish, but parasites do go through a free floating stage, at which point they are eliminated.
Additionally, fish may carry bacteria which can spread throughout the pond, killing other inhabitants. Aqua Ultraviolet UVs eliminate "bad bacteria" in pond water.
Aqua Ultraviolet UVs are also an excellent way to control algae blooms in ponds when used in conjunction with a properly sized Aqua Ultraviolet biological filter.
Electrical Circuits for Water Features
While you are working on the different phases of the pond, you should be working with the electrical part of the project, too. This should be done by licensed, qualified personnel only, and with the proper building permit. As far as your power source for your project, an existing exterior receptacle is the easiest, most convenient point of attachment. An interior receptacle will also work: simply drill a hole the size of a threaded pipe adapter out the back of the junction box from the inside of the house, through the exterior wall covering, and attach the conduit to the J-box . Even better is taking the circuit from the main panel box of the house. If you need 220 service for the pump, you must have room in the panel for a new breaker and then create an access to the panel for the new circuit.
When you run a circuit out to the site of the water feature from your power source, whether above or below ground, use 3/4” or even 1" conduit minimum. Make sure the receptacle for the pump ends up within the reach of the pump’s power cord, but still hidden from view, behind the waterfall or plants. To shield the pump’s power cord from rain or sprinklers, install a clear, waterproof cover. Using 3/4” or 1” conduit, and stranded, 12 or 10 gauge wire makes wire pulling much easier, especially when there are numerous turns in the conduit and long runs to pull through. Pull an extra hot wire or two for future lighting or auxiliary circuits while you’re at it; it will make things easier for you. Underground conduit must be schedule 40 PVC plastic pipe installed to the depth specified for your area in the code (usually 18” minimum). Above ground should be galvanized EMT conduit and fittings or per applicable code. If the pump is running continuously, no timer is required; you may want install a switch only. Otherwise a basic Intermatic mechanical timer is all you need for the simplest and most reliable operation.
The water feature should be properly grounded for maximum safety. In addition to the normal grounding to the main panel via metal conduit or grounding wire inside plastic conduit, a solid copper wire, # 8 minimum must lead from a clamp on the rebar grid in the concrete pond shell to the exterior ground terminal on the pump itself. Check local codes and confer with your building inspector to confirm this point. All of the previous information on the electrical installations is not meant to replace careful study of, and compliance with your local area’s electrical codes. The information is a general guide pertaining to water features only and is not represented by me as being all inclusive. I disclaim any responsibility for any problems you might have in this regard.