uv lights.


leo

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Good morning. I'm new to this forum. Our pond is 2400 gals, we do have a high fish load, and the pond does get sun approx 75% of the day.We usually have a fish "give away" each year to lower the fish population.We have koi and goldfish.We have a 2100 filter with a 2500 gpm pump and a 1400 filter with a 1750 gpm pump. The top of our waterfall is approx 3 feet above the water.I want to add a UV light to cope with the ever growing algae problem we have been having. Any suggestions on the size of the UV we need?. I have done some research and I"m a bit confused on the sizing. Also the lenght of the flex tubing from pump 1 is 18 feet of 1 1/2 tubing ..pump 2 lenght is 12 of 1 1/4 flex tubing to the pressurized filters. The pond stays clear early in the season but as the weather warms it get very cloudy, we do have pond plants and aeration
 
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Welcome leo!
Excess algae will grow when there are too many nitrogenous nutrients available for your filter setup to process.
The algae is actually protecting your fish from unhealthy water conditions.
If you use UV to destroy the algae, you are leaving your fish open to unsafe water conditions.
I would suggest improving your mechanical filtration routine rather than killing off the algae with UV.
Detritus trapped within a mechanical filter will start to decompose within 48 hours and deposit nitrates to the pond after that.
Nitrates fuel algae growth.
 
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I have to agree and disagree with Mitch. If you can't get rid of the algae in a reasonable amount of time then a UV light is the guaranteed way to go. You can spend the summer looking at the top inch of green pond water or you can clear it up and keep it that way in a week. My pond is about the same size as yours and the one I bought works great. I don't keep it on all the time, only when I need it.
 
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I have to agree and disagree with Mitch. If you can't get rid of the algae in a reasonable amount of time then a UV light is the guaranteed way to go. You can spend the summer looking at the top inch of green pond water or you can clear it up and keep it that way in a week. My pond is about the same size as yours and the one I bought works great. I don't keep it on all the time, only when I need it.
I agree with you that too much algae will need intervention.
PH swings and low O2 levels can be a consequence of too much algae.
 
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Hi Leo.
(adding to MitchM's advice) How many fish and roughly how long are they on average in your 2400 gallon pond? my experience is that if I can get a lot of biological filtration going then I get no algae in summer. I use no chemicals and no UV filter in my pond and never have algae in summer. I always think that algae is the evidence of too much nitrogen in the water. so if you remove the algae you will need to control the nitrogen anyway. So basically controlling the nitrogen first will probably stop the algae.
 
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I my opinion a UV light is a must have option to have if you want to have clear water all the time, especially if you have a heavy fish load. What the others have said about nutrient balance is very important, but at times things can get out of balance and a UV system comes in handy. If you kill off the algae in the water chances are there is still plenty of algae growing on the liner etc. If your bio filter is adequate you should only need to use it a couple times a year. I think Aqua Ultraviolet makes the best UV systems out there, although they are a bit pricy compared to other brands. I'd rather spend the extra bucks once rather than buying a cheaper brand twice.
 
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UV lights obviously work, but when you kill algae in a pond (without removing it) you're just creating more organic matter, hence feeding more algae growth. Get to the bottom of the problem and you'll have a long term fix without having to invest in - and maintain - a UV. In most cases that means upping your bio filtration or reducing the source - i.e., lowering your fish load, feeding less, removing more organic material.

I also question what else you're killing with the UV - lots of microscopic life in your pond that you may lose as a result. Some people swear by Iongens to take care of string algae - yes it works, but it works by adding copper to your pond which can be toxic to your fish. Work to find a natural balance or you will constantly be making adjustments to balance the last adjustment you made.

Just an opinion - as you see from this thread, reasonable people can disagree!
 
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sissy

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welcome and maybe some is caused by over feeding and overloading pond with fish .I do use a uv but only for a month or so during the pollen season .I have not had a chance to hook it up yet .I also use koi clay to buffer the water ,I think that helps more than a uv
 
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welcome and maybe some is caused by over feeding and overloading pond with fish .I do use a uv but only for a month or so during the pollen season .I have not had a chance to hook it up yet .I also use koi clay to buffer the water ,I think that helps more than a uv
Agree 100%. I use my UV as a last resort and not as a permanent solution to an inbalance problem. I also use koi clay religiously when the pond is active. I consider koi clay the magic additive.
 
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Agree 100%. I use my UV as a last resort and not as a permanent solution to an inbalance problem. I also use koi clay religiously when the pond is active. I consider koi clay the magic additive.
I would like to learn something about koi clay, I've never used it. My PH is high, but stable, will koi clay cause flucuations in PH ?
 

sissy

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does nothing to PH and you can get it on ebay ..Food grade is good for humans also .I buy 6 lbs' at a time .It is great for fish health and digestion and color and growth .I have used it since I built my first pond back in 2005 .The clay will cloud up the water for awhile but then you will look and your water will be crystal clear .It kills algae because the algae cannot feed .But first you need to test your water to see what is causing your problem .I use tons of aeration all the time .
 
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does nothing to PH and you can get it on ebay ..Food grade is good for humans also .I buy 6 lbs' at a time .It is great for fish health and digestion and color and growth .I have used it since I built my first pond back in 2005 .The clay will cloud up the water for awhile but then you will look and your water will be crystal clear .It kills algae because the algae cannot feed .But first you need to test your water to see what is causing your problem .I use tons of aeration all the time .
ive a small air pump with an airstone attached its for an aquarium should i utilize it in my new pond then
 

addy1

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I my opinion a UV light is a must have option to have if you want to have clear water all the time,
I disagree, I do not have a UV light never have green or cloudy water, only filter with pea gravel and plants (bog type filtration)

This is the pond clarity with the bog just starting to grow this season.
Capture.JPG


This is mid summer, 5 foot deep area, my ponds are full sun
20160912_122713.jpg
 
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I also don't think a UV helps get things back in balance. I look at algae growth as a symptom. It's telling me something about the condition of my pond. If I use a chemical or a UV light to clear the pond, that only deals with the symptom - it doesn't get to the root cause. And at the same time, I believe it throws something else out of whack - kind of like taking a medication that deals with one symptom but leaves you with a side effect that's just as troubling. If you have an overloaded pond, I would address that. If you don't, eventually nature will.
 
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Interesting thread! I wonder what the differences are in the ponds that need an algae cure and ones that don't have algae. In my case I have to contend with over 100 degree F summers (up to 45C) recently. And full sun. No algae and no chemicals and no UV filter! I have a fairly large pond with 12 fairly large koi in it. biggest Koi are about 18inches long. I have a large gravity fed filter with about 4 cubic feet of bioballs and actively growing plants. I end up with very low levels of nitrogen in the water so it cannot support algae growth. No surface runoff can enter the pond either. my main waterfall is pretty active and I have a secondary one at the other end of the pond. I have no mechanical filtration (sponges or foam etc). my water is so clear you can see sand grains on the bottom of the pond. I think importantly in my set up the water passes through the filter very slowly as it is a big cross-sectional area for the water flow. It is not pressurised at all.
As I said at the start an interesting discussion (really important one as well).
 

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