AA Aquarium Green Killing Machine UV Sterilizer Review – Video

The AA Aquarium Green Killing Machine Internal UV Sterilizer System is a submersible UV Sterilizer with a power head. UV sterilizers destroy algae, bacteria, and parasites floating in the aquarium water.

It does this using a power head and UV bulb. As the algae-infested water flows through the UV bulb, the UV light kills the bacteria and returns the clean water to the tank. Here’s why it’s one of the best UV sterilizers for aquariums.

How Does It Work?

The Green Killing Machine comes with a small power head and a sealed UV light fixture. The device uses a DC power supply connected to a controller which then connects to the power head and the UV light fixture.

The 9-watt sterilizer filters up to 50 gallons of water. For larger tanks, buy the 24-watt version. Set up is easy and takes about five minutes once you follow the instructions in the booklet.

The UV Sterilizer outputs disinfecting radiation at about 254 nm using the power head to draw in water. It uses a zigzag mechanism to allow maximum exposure of the water to the UV light thus destroying more harmful microorganisms.


  • Affordable
  • Makes water crystal clear in about 2-weeks


  • Quite big

How To Set Up

  • Before you begin, turn off the air bubbler in your aquarium (if you have one). Take the air bubbler’s hose and attach it to the Green Killing Machine UV Sterilizer (skip this step if you do not have an air bubbler).
  • Place the Green Killing Machine Sterilizer into the aquarium and use the suction cups to stick it to the fish tank wall.
  • The entire device, except the control box, should be underwater. Place the control box on the outside of the aquarium near the same place you attached the Green Killing Machine.
  • Please do NOT place the control box to the top of the tank or any other location where it may come into contact with water.
  • Connect the two-pin wire from the Green Killing Machine sterilizer to the two-pin plug on the control box.
  • Connect the black, female wire from the DC power adaptor to the control box.
  • Plug the DC adaptor into a wall outlet.
  • Turn on the air bubbler.
  • Turn on the Green Killing Machine.
  • Use the LED indicator on the control box to verify that it’s working.

What I Like Most About It

It’s affordable and very good at clearing up the tank. It’s also easy to install because the pump and light connect, there’s no need for any plumbing. All you have to do is plug it in, and it’s ready to start cleaning your aquarium.

Is It Effective?

Yes. The Green Killing Machine is effective at clearing up green cloudy aquarium water and destroying harmful bacteria and pathogens.

It usually takes between one to two weeks to clear up the water in your aquarium depending on the severity of your problem.

To speed up the process, you can do a partial water change after you install and set up the sterilizer in your tank.

Before And After Pictures

Video – Green Killing Machine Review

Will It Kill Good Bacteria?

Yes, the AA Green Killing Machine kills the good bacteria also, but only the bacteria that goes through the machine. Most of the good bacteria in your tank are on the filter media or in the substrate so they should be safe.

Will It Harm Fish or Plants?

No, the Green Killing Machine will not harm your fish or plants, but it will render medicines ineffective so unplug it when treating your tank or fish with medication.

How Long Does It Last?

The manufacturer recommends using it 8 hours per day if you want the bulb to last 6-9 months. The longer you run it, the sooner you have to replace the bulb.

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