Aquarium and Pond UV Sterilization Information Directory

Also, it is recommended to install the UV sterilizer when the aquarium is cycled.
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UV Sterilization is also effective for controlling suspended algae (green water) in ponds in part by clumping the algae which then falls to the bottom or is filtered out (along with proper filtration such as Veggie Filters/pressurize filters which are just as important as a UV Clarifier/Sterilizer). This of course assumes your aquarium or pond has a healthy bio filter.
Below is a video from BRS which does a good job of explaining the aquarium UV sterilizer.
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This is easily the most important simple aspect of proper UV Sterilizer set up and all the gimmicks (like “twists” and “wipers”) will not help a poorly installed UV with high flow rates of water passing through the unit without proper exposure time at the correct distance from the UVC Lamp/Bulb.
In fact this is where most UV Sterilizers installed in ponds fall short as pond keepers will place (as an example) a 9 watt UV powered with a 1000 gph pump which is 2-4 times the effective flow rate for a pond installation (often as per very poor directions by the manufacturer).
This problem is also common among reef aquarists with high flow rate sump pumps attached to UV Sterilizers incompatible with the flow rate, resulting in the common and incorrect statement that "the UV Sterilizer was useless". For a  up to date article about aquarium and pond uv sterilization, please visit this site:
Photo provided by FlickrAquarium-Pond UV Sterilizer History (from my professional perspective dating back to 1978)
Photo provided by FlickrI continue to follow the threads on forums, aquarium articles, and blogs about UV Sterilization.
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Aqua Ultraviolet’s UV Sterilizers have been used by public aquariums, importers and hobbyists alike to control bacteria, protozoa and parasites, reducing the spread of fish disease. In a confined environment like an aquarium UV and filtration are essential. When using a UV Sterilizer in a home aquarium, the UV unit should be placed last in the filtration line. You want to first filter the aquarium water through your and then run the water through the UV device before returning the water to your fish tank. By first removing the solids in the aquarium water with your mechanical filter (canister filter, etc), you are helping your UV unit to attain maximum operational efficiency.
The aquarium UV Sterilizer is a water filtration device that uses an ultraviolet light bulb to kill microscopic organisms that are free floating in the water. Parasites, viruses, algae and bacteria (good and bad) are the type of things that are "killed" after passing through the ultraviolet sterilizing unit. UV sterilizer devices can be used on swimming pools, in liquid factories (think beer) and in the home aquarium using an aquarium UV sterilizer. Some large water purification centers employ some sort of UV sterilization on the outgoing water. These sterilizer units are also sometimes used in outdoor ponds to help control algae growth and they seem to do a decent job.The plus side to these submersible UV Pump/Filters is the need for no additional plumbing in aquariums or ponds, not that splicing a line for a TMC or Terminator UV is all that difficult (with ponds though, extra devices such as UVs can sometimes be a bit more of a plumbing project).

However the another entry into the field of Internal UVs are still incorrect as per their flow rate (& construction); The AquaTop UV Sterilizer Pump 3, 5, 7, & 9 watt are actually no better than the Submariner or similar early generation Internal UVs (please read more about these later in the article).The first generation Internal UV Filter/Pumps created a lot of excitement, at least among many aquarium maintenance professionals I knew/know. However as these were purchased and then utilized in aquariums or ponds, their short comings became apparent.

In particular the problem of leakage causing electrical shorts and often destroying the UV.
This problem was even more prevalent with the Green Killing Machine and their rather bizarre and VERY rude, condescending, & un-professional phone call to an aquarium professional friend about his reply to a comment THEY posted on HIS YouTube UV Sterilizer video tells me this is NOT a company I could recommend -EVER.The AAP 13 Watt CUP-613 Pump/Filter Model performed well in initial tests, however the AAP 9 Watt UV CUP-609 Pump/Filter Model uses the same 528 gallons per hour manufacturer rated water pump as the 13 watt model which is generally too high for level 1 UV Sterilization.
HOWEVER later tests following adjustments made by AAP of this UV Sterilizer in configuration showed only a 160 gph flow rate in an aquarium in the vertical configuration which is appropriate for level 1 sterilization (9 times 25 = 225 gph or less).
Please note that these "correct flow rate" models are NOT sold on eBay, Amazon, etc., only by professional sellers such as AAP.

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