Green Killing Machine

[jeffchapok]

My water in my 60 gal was somewhat cloudy so I added a 24 Watt green killing machine and within 2 days the water was crystal clear. I run it 24x7.

 

[Amateur Reefer]

Has anyone else had problems with these? Mine seems to have just stoped working.

 

[Be102]

Has anyone else had problems with these? Mine seems to have just stoped working.

How long have you had yours? I’ve had mine almost a year I’d say and it seems to be doing well (or I believe it is as the green light is on)

 

[Amateur Reefer]

6 months? The green light is on, but nhing is coming out of the pump . . .

 

[Be102]

6 months? The green light is on, but nhing is coming out of the pump . . .

Perhaps the flow got messed up? Is something in the input? Sorry I don’t know much about these things just trying to see what could go wrong since from my understanding is just a light and a pump? Do you think your pump died?

I only really bought mine because I heard good reviews when people contacted the company and I didn’t want to spend hundreds of dollars on one!

 

[Neil S.]

6 months? The green light is on, but nhing is coming out of the pump . . .

I've had mine do exactly the same thing. If your system feels like the pump is running but nothing is coming out then the pump is not priming properly. Try this, (it's worked for me in this situation) detach the pump from the light unit, hold the pump under the water and plug it in, (Be safe, keep the plug hand dry). This should allow the pump to prime properly, then while running, reattach the pump to the light unit and it should now be working.

Points to note: This device only seems to work properly in a vertical position, the whole unit works better submerged, with just the output above the water. If you don't have the water depth then at the minimum the entire light unit should be under the water.

Hope that helps.

 

[dochou]

Hello,

@Montiman, I have volunteered for almost ten different aquariums when I was in my undergrad program. We used these mainly has our uv sterilizer. My water is crystal clear and I do not have any issues with alage, hair algae or bubble alage. In light to your response how do you know the more expensive ones are even working? M

I have used these in a laboratory environment while conducting my thesis research during my undergrad years. The main thing one must remeber is that, it only works if it had the correct amount of flow and time circulating around the bulb. Do the fact this one has its own power head that controls its flow for the exact time frame is a plus. Most of these expensive ones you must tap into your return pump.

Last but not least I did the math on it as well, in which im pretty darn good at. so with that said let’s go deeper into this subject with math and scientific proof. So we all know our aquarium water is packed with micro-organisms—bacteria, plankton, algae, fungi, parasites and other microscopic life – hundreds or thousands of times what is found in nature, the water is full of microscopic non-living debris—even if the water looks clear. Now since we know this as default we can then know that UV sterilizers don’t sterilize aquarium water—they can only reduce the population density. If we keep reducing the population, we will eventually either get rid of it temporarily, and or reduce where it’s not a problem.

We all know, in order organisms to be killed by UV, they must be exposed to the radiation at a certain strength for a certain amount of time. Because aquarium water contains so much suspended matter, it is easy for the organisms to “hide” behind other particles and organisms as they flow past the UV light. This reduces exposure to the UV radiation and limits its effectiveness. At the same time these “bugs” are reproducing in the aquarium. This basically helps kill the free floaters, they can’t hide all the time. Is this a perfect solution and fix all, no but if added to the equation then it certainly reduces those parasites and alage.

Now that the basics are covered let’s get scientific here. We know that a disinfection method that uses short-wavelength ultraviolet light to kill or inactivate microorganisms by destroying nucleic acids and disrupting their DNA, leaving them unable to perform vital cellularfunctions. Uv is used in a variety of applications, such as food, air, and water purification, not just fish tanks. Now, V-C light is weak at the Earth's surface as the ozone layer of the atmosphere blocks it. The uv devices can produce strong enough UV-C light in circulating air or water systems to make them inhospitable environments to microorganisms such as bacteria, viruses, molds and other pathogens. UVGI can be coupled with a filtration system to sanitize air and water. So yes there is a difference if they are used properly and it doesn’t matter if you spend 70, or 700 uv is just that uv, what matters is well the math and flow.

UV light is electromagnetic radiation with wavelengths shorter than visible light. UV can be separated into various ranges, with short-wavelength UV (UVC) considered "germicidal UV". At certain wavelengths, UV is mutagenic to bacteria, viruses and other microorganisms. Particularly at wavelengths around 260 nm–270 nm, UV breaks molecular bonds within microorganismal DNA, producing thymine dimers that can kill or disable the organisms.

By doing the simple math of,
UV dose µWs/cm² = UV intensity µW/cm² x Exposure time (seconds) we can determine what we need for our tank to be effective. Now to be very effective we need to apply some basic concepts which are, 1.) Flow rate (contact time)
2.) Transmittance (light reaching the target)
3.) Turbidity (cloudiness)
4.) Lamp age or fouling or outages (reduction in UV intensity)

The green killing machine well tells you when the lamp age is well old and needs to be replaced, it also controls the flow rate, it also forces the light to reach the target through the uv chamber, and last turbidity makes the water crystal clear.

So based on the math and four basic requirements, one can assume yes it works. It’s the same as if you water to dirt it makes mud, or water to coffee grounds, plus heat and time makes coffee, am I wrong?

To further this UV intensity is specified for each lamp at a distance of 1 meter. UV intensity is inversely proportional to the square of the distance so it decreases at longer distances. Alternatively, it rapidly increases at distances shorter than 1m. In the above formula the UV intensity must always be adjusted for distance unless the UV dose is calculated at exactly 1m from the lamp. Also, to ensure effectiveness the UV dose must be calculated at the end of lamp life (EOL is specified in number of hours when the lamp is expected to reach 80% of its initial UV output) and at the furthest distance from the lamp on the periphery of the target area. Some shatter-proof lamps are coated with a fluorated ethylene polymer to contain glass shards and mercury in case of breakage; this coating reduces UV output by as much as 20%. This shows and tells when to replace our bulbs and to find the correct set up.

To further enhance this let’s figure this in, The degree of inactivation by ultraviolet radiation is directly related to the UV dose applied to the water. The dosage, a product of UV light intensity and exposure time, is usually measured in microjoules per square centimeter, or equivalently as microwatt seconds per square centimeter (µW·s/cm2). Dosages for a 90% kill of most bacteria and viruses range from 2,000 to 8,000 µW·s/cm2. Larger parasites such as cryptosporidium require a lower dose for inactivation. As a result, the U.S. Environmental Protection Agency has accepted UV disinfection as a method for drinking water plants to obtain cryptosporidium, giardia or virus inactivation credits. For example, for one-decimal-logarithm reduction of cryptosporidium, a minimum dose of 2,500 µW·s/cm2 is required based on the U.S. EPA UV Guidance Manual.

So based on studies done by labs and unversities and the fact I have conducted some of my own, yes I know they work. Are they a fail safe no, are they perfect of course not, but prevention is important, if we can help prevent an out break along with other steps, why would we not incorporate the uv sterilizer? I do agree that if left on for too long of a period, it can harm and reduce good bacteria. This is why I turn mine off after two weeks for a period of time.

From your last post it seems you have studied this as well, is there anything I have missed or that you can add so others will have a better understanding? P.s I am super sorry for the short novel I just posted here.

Sarah

Great write up. Thank you. Just what I was looking for.

 

[Michelle001]

Hello,

As a matter of fact I love it and went to two of them just because my tank is so large. I have had very little algae no fish disease (knock on wood), and they have been maintence free for about a year now. I would not change them out, they honestly work amazing.

As you stated earlier, not everyone can afford the expensive up’s. I am one of those and have been told i need one as I am struggling with ostreopsis dinos. I have an 84g tank. Would the green killing machine be an affordable option for me?

 

[rockdiver]

I might get one. I did find a UV a good one for an affordable price but once I received it the thing is BIG and I cannot fit it under my tank ! I can make a hole thru the wall but am reluctant to do that.
So I might just hold onto it and buy one of these.
This is an affordable option imo, but I think it is only good for algae and stuff not any disease type stuff like ick,velvet ect. But maybe someone will chime in on that

 

[rockdiver]

Well I did go get one the 24w
Easy to set up 25% off since I ordered online and picked up. Easy to setup. Only issue I have is it sticks to the inside using suction cups and well they suck lol. So I'll figure that out today. It is to big for my sump so have it in the DT, not thrilled about that. I'll see if it does anything. My tank is usually clear but the sand gets dirty in 2 days so we will see in a few days. If this works I may have incentive to set up the big one I have if this small one provides results.

 

[dochou]

As you stated earlier, not everyone can afford the expensive up’s. I am one of those and have been told i need one as I am struggling with ostreopsis dinos. I have an 84g tank. Would the green killing machine be an affordable option for m

@Michelle001 I think it depends on what you want it for. Personally, I bought one after reading @Sarah24! 's write up.
I needed UV to clear a bacterial bloom that would not go away. 2 days after using it, my water was chrystal clear. So it worked for me. It may be beneficial foralgea problems too. I doubt it will be strong enough for fish diseases though.
I bought the 24 watt version for my 150 gal tank.

 

[Sarah24!]

As you stated earlier, not everyone can afford the expensive up’s. I am one of those and have been told i need one as I am struggling with ostreopsis dinos. I have an 84g tank. Would the green killing machine be an affordable option for me?

Hello,

Theses would work fine for you for what your seeking. But they do not have ozone and or strong enough to take down marine ick or velvet etc.
They do work very well and I did upgrade to a unit with ozone to handle that. With that said I don’t use the two I have. My other uv has the option of ozone (very dangerous if you don’t know how to use it), and a much much stronger class A uv which will kill viruses etc. if your trying to keep alage gone they work well for that, but you also need to have a good clean up crew as well. But compared to ones you can buy now for like 400 ish these are much cheaper and do the same. They are a class c which most of the ones you can buy are that. The best part is they control their own flow and they are short. My new one won’t fit in my sump, it is on the back side of the tank. The longer the uv period the better.

 

[NJBillyV]

Why not run a UV? There are no disadvantages and plenty of advantages.

It kills all kinds of unwanted stuff and keeps your tank crystal clear. I bought a cheap Odyssea 18W ($49) and connected to my return hose and my tank has never looked better. Every once and a while I slow down my return pump so I get a longer dwell time. And, I no longer constantly stress about what's going to attack my tank.

 

[chippwalters]

I had a really bad breakout of dino in my 10 gallon system. I siphoned off all the dinos each day only to see more return the next day. Like some other nuisance algaes, dinos release from objects and float into the water column at night. Adding a GKM to the display tank and running it 24/7 wiped out the dinos in under 2 days. Huge success! I left it in for another month, then took it out. I'm a big fan. I had a larger aquarium with an inline UV sterilizer coming from the return pump and it never did much, plus I never knew when the bulb was good. These guys have solved all the problems. Definitely worth the money!

 

[Lovergasoline]

I'm posting to this thread because there's a lot of info gathered here on the Green Killing Machine.

I have a question on the shelf life of the UVC replacemnt bulb (9w) for the Green Killing Machine (bought new on Amqzon in Nov 2023). The box my bulb came in has a sticker: NEW/EXP 01-Jul-2025. I wasn't aware that the raw unused bulb had a limited shelf life, and in this case about 1 yr. 8 mths from date of purchase.

Does that sound right: that bulbs expire unused and stored in a box? And under a two year shelf life?
Or is this an old unit being sold as new?

PS: I've never left The Green killing Machine running 24/7 as a prophylactic measure. I only install it if I get an algae bloom and then leave it running for about a week or so unitl the water clears, after which I remove it.
This is my third bulb, the last bulb was only used for less than 30 days before dying. Wondering if that sounds normal, or if I'm being sold already aged out, near expired bulbs?

 

[Randy Holmes-Farley]

FYI, a number of reefers have associated the green killing machine with elevated antimony in the water, and folks thinking of getting one might search on that and see folks experiences.

I do not know anything about bulb expiration, but it would be an exceptionally poor bulb design that went bad in 2 years sitting in a box.