My main pump is 650 g/h flow rate which is in the 3rd compartment of my sump. My UV max flow rate is 1750 l/h and it is fed by a 1000 l/h power head. running it 24 - 7 will it be effective on this set up of almost 300 gals. the uv draws from and empties back into the 3rd compartment as well.
UV Useage
- Thread starter Robinhud
- Start date
Most any wattage of UV light will cause free algae to clump up preventing green water. But if you want to kill bacteria and viruses, you need to have a high wattage UV light and a slow flow rate through the UV light tube. The thickness of the water column next to the UV bulb also plays a role. I have yet to see an equation which tell you how to size the bulb, water film thickness, and flow rate to guarantee you are killing viruses. It is probably out there somewhere. I'd suggest finding a UV light manufacturer who has the information on line. Of course it will be specific for their equipment which will already have a defined water layer thickness.
Places like Petco and Petsmart have huge UV lights in their recycle systems and they do work. But I believe they are putting 100% of their water through the UV light system. If you are putting only a portion of the recycle stream, the system will only be good to prevent green water.
Places like Petco and Petsmart have huge UV lights in their recycle systems and they do work. But I believe they are putting 100% of their water through the UV light system. If you are putting only a portion of the recycle stream, the system will only be good to prevent green water.
uv rating of 1750 l/h = 462 g/h, pump rating of 1000 l/h = 264 g/h
at this flow rate I am getting a good dosing of uv into the water and I am completely turning over the water 21 X in a 24 hour period. I am thinking that should put a real crimp in the spreading of a bacteria. No it is not perfect, money is a factor, but the resistance of healthy fish should make up the difference. water quality and low stress environment is also factors for good healthy fish. I hope I am doing a good job at both. Frank thanks for your help, I am not debating you but expressing my train of thought for your oppinion as well as others to further my own experience. Thanks again
at this flow rate I am getting a good dosing of uv into the water and I am completely turning over the water 21 X in a 24 hour period. I am thinking that should put a real crimp in the spreading of a bacteria. No it is not perfect, money is a factor, but the resistance of healthy fish should make up the difference. water quality and low stress environment is also factors for good healthy fish. I hope I am doing a good job at both. Frank thanks for your help, I am not debating you but expressing my train of thought for your oppinion as well as others to further my own experience. Thanks again
JLW
CCA Members
In order to figure out what it's doing, you need to know a little more information. It's not just the rating of the UV, as those are -- for the most part -- pretty much useless as anything but a guideline for water clarifying. You'd need to know your actual flow rate through the UV, its velocity, and the amount of contact time, which can be figured out from the flow rate and the length of the UV tube (assuming its linear; if its twisty or something, you can still do it, but it'll be more complicated). This can give you the exposure time.
Next, you'll need to know the wattage of the UV bulb itself, and get an idea of its efficiency. A lot of people forget that a UV bulb is a fluorescent bulb and needs to be replaced at least once every six months, even if it continues to light. At about the 6 month mark, you're at 80% efficiency, and it drops precipitously from there. After a year, your bulb is utterly worthless. Keep in mind that this also assumes your quartz sleeve is good, clean, etc.
Lastly, you'll also need to consider the water clarity and thickness of the water column going through the UV unit. If you have a lot of tannins, if your sterilizer is very thick / wide, etc., you'll have a less efficient sterilizer (i.e., if you stick a UV tube in a 55-barrel, the light is going to be mostly absorbed by the time it reaches the edges, but if the water just skins over the bulb, it'll be tremendously effective, no matter what... you'll also probably overheat.
You can find figures on the amount of contact time at various UV energy levels for killing all sorts of things, from viruses to Matt Quinn and other pests. (Sorry Matt). You may need to make some guestimates, and you may need to convert wattage into something actually useful, but it's not too difficult.
I would say, if you're running at about half the recommendation on the flow rate, you're probably going to reduce parasites, algae, and bacteria, but I doubt you'll have any real effect on viruses. You'll also not completely eliminate other pathogens, just reduce them. That can be enough, though. (And, as Frank mentioned, if 100% of your water isn't going through the sterilizer, no matter how effective it is, it won't eliminate these.)
Keep in mind that UVs do not effect algae growing on the glass or decorations, and can actually make the problem worse. If you have green water, there's a problem with the tank that needs to be addressed -- green water is like the "Check Engine" light on your car. You can figure out what the underlying cause is -- too much light, too much fish, too much fish food, etc. -- or you can put a piece of black tape over the light (the UV) and just keep driving. A lot of us do this and are just fine, but it could just result in a major outbreak of surface algae, as they are now able to take advantage of excess nutrients, or excess light (made easier by your crystal clear water!).
Next, you'll need to know the wattage of the UV bulb itself, and get an idea of its efficiency. A lot of people forget that a UV bulb is a fluorescent bulb and needs to be replaced at least once every six months, even if it continues to light. At about the 6 month mark, you're at 80% efficiency, and it drops precipitously from there. After a year, your bulb is utterly worthless. Keep in mind that this also assumes your quartz sleeve is good, clean, etc.
Lastly, you'll also need to consider the water clarity and thickness of the water column going through the UV unit. If you have a lot of tannins, if your sterilizer is very thick / wide, etc., you'll have a less efficient sterilizer (i.e., if you stick a UV tube in a 55-barrel, the light is going to be mostly absorbed by the time it reaches the edges, but if the water just skins over the bulb, it'll be tremendously effective, no matter what... you'll also probably overheat.
You can find figures on the amount of contact time at various UV energy levels for killing all sorts of things, from viruses to Matt Quinn and other pests. (Sorry Matt). You may need to make some guestimates, and you may need to convert wattage into something actually useful, but it's not too difficult.
I would say, if you're running at about half the recommendation on the flow rate, you're probably going to reduce parasites, algae, and bacteria, but I doubt you'll have any real effect on viruses. You'll also not completely eliminate other pathogens, just reduce them. That can be enough, though. (And, as Frank mentioned, if 100% of your water isn't going through the sterilizer, no matter how effective it is, it won't eliminate these.)
Keep in mind that UVs do not effect algae growing on the glass or decorations, and can actually make the problem worse. If you have green water, there's a problem with the tank that needs to be addressed -- green water is like the "Check Engine" light on your car. You can figure out what the underlying cause is -- too much light, too much fish, too much fish food, etc. -- or you can put a piece of black tape over the light (the UV) and just keep driving. A lot of us do this and are just fine, but it could just result in a major outbreak of surface algae, as they are now able to take advantage of excess nutrients, or excess light (made easier by your crystal clear water!).
