AA Aquarium Green Killing Machine Internal UV System

By AA Aquarium
Rated 4.4385 out of 5 stars


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$50.85 (-27%)Chewy Price
$69.99Chewy Price
In Stock
FREE 1-3 day delivery

About This Item


  • Promotes dazzling, clear water in your finned friends’ abode.
  • Designed to be easy to install—no tools necessary!
  • Helps remove murkiness from aquarium water.
  • Helps create a green-water-free home for your fish!
  • Comes with a powerhead.

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Play Video: Learn More About AA Aquarium From Our Team of Experts
Learn More About AA Aquarium From Our Team of Experts

Frequently Bought Together

AA Aquarium Green Killing Machine 9 Watt Replacement Bulb
Rated 3.5 out of 5 stars
$34.99Chewy Price
API Algaefix Algae Control Aquarium Solution, 16-oz bottle
Rated 3.5263 out of 5 stars
$16.99Chewy Price
Total Price: $102.83

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Fish TypeMarine Fish, Tropical FreshwaterBetta, GoldfishMarine Fish, Tropical Freshwater

Questions & Answers

44 Customer Questions

how can you tell if the light is actually on? you cant see it at all , it is sealed up. Pump has flow, but want to be sure its on
Answer by kittenpapaJul 18, 2020
When your water goes from much to crystal clear. This thing is a miracle and took my new 75 gallon tank from heartbreak to crystal clear in a few days.

My water is crystal clear now If I have no timer how often should I turn on machine
Answer by ChewyNov 11, 2020
UVC bulbs typically last about 6-9 months in constant use. Some bulbs can last up to a year. To lengthen the service of your bulb, we suggest once your water is sparkling clear for 7 full days, start using your UV on a limited as needed basis. Run it with your light timer or only on weekends, etc.

Does it kill parasites like Ich?
Answer by ChewyNov 09, 2020
This sterilizer does not kill parasites.

After I do a partial change, I add good bacteria. How long should I keep the sterilizer turned off?
Answer by ChewyFeb 23, 2021
There are times that you do not want to operate your Green Killing Machine 24/7. We would recommend turning the GKM off for 1 week to allow the added good bacteria to grow on the bio filters. After that, use the GKM as needed to maintain desired water clarity.

ReviewsWrite a Review

Rated 4.4385 out of 5 stars
244 Ratings
Would recommend to a friend

244 Customer Reviews

Rated 1 out of 5 stars
By Lee on Nov 26, 2023

Spend $40 and They Send Me A Broken UV Light

So, I finally got the chance to set up this 9 watt UV light in my 65 gallon aquarium today, only to find out that the power head is the only thing working on this unit, the UV light is broken!!! So, basically for $40 I just get a working power head and not a UV light!! SO MY ADVICE TO EVER6 OUT THERE THINKING ABOUT BUYING ONE OF THESE UNITS FROM "CHEWY", DON'T GO TO YOUR LOCAL PET STORE!! NOW I AM STUCK WITH A POWER HEAD AND NO UV LIGHT!!!

Rated 5 out of 5 stars
By Pat on Oct 1, 2023


I was having problems with algae bloom in my 36 gallon tank. Used chemicals, did water changes and changed filters often. Reduced the amount of food I was feeding and still had a green tank. A friend suggested a UV sterilizer and I chose the 9 watt, up to 50 gallons. While waiting for it to come, the 75 gallon tank I’ve been wanting went on sale so bought it. Set it up just in time for the sterilizer to come and surprisingly for the 9 watt, the tank stayed mostly clear. It made me a believer, I went ahead and ordered the 24 watt and now my water is crystal clear. Moved the 9 watt to the 36 gallon and it’s on its way to clear. Even if you’re not having major issues, I highly recommend getting one of these!

Rated 5 out of 5 stars
By Fish on Sep 21, 2023

Algae bloom

The Green Killing Machine worked perfectly as advertised. My mixed reef tank had an algae bloom to the point of not being able to see the fish unless they were within an inch of the glass. In 3-4 days the water was almost clear if green. It was an easy intank install with suction cups. I wold purchase it again. FedEx delivery was a day slow but that isn’t unusual where I live.

Rated 5 out of 5 stars