AA GKM24W Internal UV for Aquariums up to 120Ga,Black

Before I purchased the Green Killing Machine I purchased fluval's in-line sterilizer. When using that product I had an outbreak of flukes, which I fought for months. I had to do a major filter tear down on my sixty gallon display tank. But thankfully, that forced me to do more research on uv sterilizers. Apparently most don't cut it, especially for parasite control. Live Aquaria has a great uv sterilizer chart that goes over flow rates and wattages that are most appropriate for your tank. (I included a screenshot of their chart, but the information is also worth a read) This particular model meets my requirements. It's flow doesn't exceed 150gph and it's wattage is high enough to control parasite populations in my tank. The only bummer about the unit at all is that it's large. And it has two ballast boxes. But in a way, that gives me confidence in the unit. Definitely a no bs system. And technically I could have gone with a smaller model (I have a sixty gallon and could probably have used the smaller model) but in the case of uv sterilizers, bigger is better. Installation is straightforward. I don't recommend turning it on and off rapidly -- when you turn it on leave it on for at least a few minutes before turning it off and vise versa (that goes for all advanced lighting systems and will help prevent a blown blub). All in all, I'm grateful that this company is producing an affordable uv sterilizer that's actually robust enough to kill algae and parasites. And I really appreciate not having to touch bulbs ever again.

Great product love it. My tank was extremely drained and it cleared it up right away.

We WERE so pleased with this product and WOULD have gladly given it 5 stars; however, it simply stopped working after merely 6 weeks (actually 40 days)! We read the troubleshooting guide and tried everything from restarting to checking all connections, etc. to no avail. What a pity! This product really works well -- WHEN the UV light is on. Now, we are extremely frustrated! Our tank is 125 gallons and although it took about 2 weeks, the "Green Killing Machine" destroyed the algal bloom exactly as promised, leaving our tank crystal clear. Our fish looked great, the tank was ultra clear and we remarked that we wish we would have purchased one years ago. This all changed, however, when we noticed that the tank was getting a bit cloudy after only 5 1/2 weeks. Figuring it was just temporary, we did not stress over it. Unfortunately, however, it only got cloudier -- and greener -- with each growing day. Troubleshooting simply revealed that the UV light stopped working. Period. Will be glad to update this post and give it 5 stars if the manufacturer/seller makes the situation "right" by fixing or replacing. However, right now we CANNOT recommend this product due to its UNRELIABILITY. What a shame.

I have a 55 gallon freshwater fish tank that just wouldn't clear up from a bacterial bloom, I let the tank try to cycle itself as I have never liked using chemicals to do what mother nature does on its own. But after 2 weeks of waiting for that to happen, I got impatient and decided to try a UV filter, and due to the severity of the bacterial bloom I went with the 24watt in hopes of it clearing the tank up faster, as you can see from picture (1) to (4), those are taken every day until it cleared. This UV filter I know will work as stated on larger tanks but may take a few more days to complete the process. As I can afford too, I will be adding these to my many tanks as I go along.

This worked and the green soup water has cleared up. Day 4 after starting the AAA Green Killing Machine the water remained full of algae. I did a 75%-80% water change and the water was clear & stayed clear. I unplugged it a week ago and the aquarium looks great! Very happy with this product.

Another update - It turned out that the problem was not the bulb so the company replaced the whole thing and its been working well ever since. The company has great customer service and is here in the U.S. I Update- I contacted the company and they said the bulb was likely defective and are sending me a new one. So I'm going from 1 star to 3 stars. If it lasts a few months I'll bump it up to 4. I ignored the bad reviews and bought it anyway. Don't waste your money. It worked well but the light stopped working after a few days use. I'd turned it off for a few days to put it on a timer and the light wasn't working when I turned it back on. For some reason I thought it came with a second bulb, so i wasn't in a hurry to replace it. It doesn't and it's too late for me to return it.

Great product my aquarium water is really clear

This device works great but has some serious flaws. The inability to see if the light truly works or has burnt out is very frustrating. This enclosure makes it near impossible to know if you fully have cleaned it. I have found that sometimes I still have bacteria grow in my water even when using consistently. It’s did work initially well and is easy to setup but it stopped working effectively very quickly.

Great product, easy to install. I was skeptic at first since you can't see the light because it's internal. It's super easy to install. It took about a week to clear out the algae bloom I had going on in my 90 gal tank.

Hard to get. No longer any supplier in Ireland and unable to import from the UK ( blocked by Royal Mail for some reason). Product description is lacking a description or specification explaining which electrical power is required ( different for USA and Ireland). Obviously need to know this when purchasing. Otherwise I found it to be a very effective product for the purpose for which it is intended.

This UV light cleared my 50 gallon aquarium of heavy algae bloom in less than a week! It was so green you couldn’t even see anything in the tank - now it’s clearer than it’s ever been! Very impressed

Got rid of the algae as advertised, but stopped working after a month ... right after the return window closed. I ordered "Nutrafin A7915 Clear Water Clarifier" from Amazon and the results are fantastic. 3 days and all the algae is gone!

Water was good as new in pretty much 48 hours for a 50 gallon tank with a Yellow-belly Slider. Easy setup.