AquaTop Aquarium Power Filter w/ UV Sterilizer | PetSolutions

Aquatop PF40-UV Hang-On Filter with UV Sterilization. Suitable for aquariums up to 40-gallons
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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.
Submersible UV Aquarium Filter
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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.

Recommended Product Resource:

Reference: Solid durable construction Terminator UV Sterilizers, Clarifiers, UV Filter Kits for aquariums and ponds.
Photo provided by FlickrPlease Read these helpful articles for more about matching the correct UV Sterilizer to your Aquarium, Pond, Filter, or Pump**
Photo provided by FlickrThe picture to the right shows a AAP/SunSun Terminator 9 Watt Compact UV attached to a newer Fluval Filter in an aquarium cabinet.
Photo provided by Flickr

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.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.
First the Proprietary Heavy duty 13 watt and 9 watt UV Pump/Filter design with double O Rings seems to have solved the leakage/UVC short problem for the most part, and the flow pattern/design is also improved over earlier Submariner and similar models.

One negative is "rated" flow rate, however as per our tests this "rated" flow rate is not the actual flow rate; the actual/adjusted flow for certain proprietary units by AAP is much better for level one UV Sterilization.
The propeller design of the impeller has little head pressure which actually is better for maintaining a flow rate of 25 gph per watt in the vertical configuration.
However, the flow rate is not good enough for circulation of very large aquariums or ponds, so for this reason other circulation pumps should be utilized so and I advice to not depend upon these UV Pumps as the primary mode of circulation.