Hi, all,
I have a 100 gallon pond with one Shubunkin in it. It has been up and running for about 2 months, now, and except for a nitrite spike in the beginning, I've never had the numbers go whacko while it was cycling. My params are always at 0, and my PH stays between 7.8 and 8.2. My fish is growing like crazy and seems very healthy, but my water has turned murky and green. My bio-filter is not clearing it up even with water changes, so I was thinking about getting a UV sterilizer. I have seen them advertised with either a powerhead or pump and I don't know which is better or even what the difference is? I've been told that a 9W will handle my 100 gallons, but that a 13W would be even better. Could someone tell me how these work, how they are installed and which is best, a powerhead or a pump? Thanks so much in advance.
Lynn

If I'm not mistaken a powerhead is a pump for an aquarium and you wouldn't want this for you pond, but I could be wrong.
I have a few questions though, what size pump do you have and what kind of bio filter do you have (bio balls, filter pads, etc..). Those aren't that important I'm just curious because I would think that your filter should be doing the job after 2 months.
When doing your test of nitrites and ammonia do you allow the test tube to sit for five minutes after putting the drops in and shaking the test tube? I'm only asking this because I never used to wait, I thought it was instant and so I always thought my params were good LOL. I left the test tubes sitting one day and got a huge shock, my nitrites were threw the roof! poor fish know wonder they hated me. Anyhow, I got that figured out.
On the U.V. sterilizer. I have one, it's wonderful I think. I haven't had pea soup since I installed it. I bought one larger than I needed because my pump is twice the size I need. I wanted to make sure it did it's job. Certainly with your u.v. sterilizers you can judge what size you need by the size of pond, but if you want to make sure it's correct you need to look at the water flow it is capable of handling and make sure your pump isn't going to send the water threw too fast. The faster the water the larger the sterilizer. If you send your water threw too fast you've wasted your money. And by the way, the only thing that they do is kill the pea soup algae they don't slerilize the water unless your water is going through the u.v. light slow and you have a big u.v. light (which is great because sterile water would be easier to keep healthy fish in). U.V. lights are expensive, especially the ones that do the job the best. On another message board I read posts by people who've had their u.v. lights for a few years and they've decided they really aren't worth the money. If you have good parameters you shouldn't need the u.v. light. The u.v. light is only for spring to keep the water from pea soup and if you need it throughout the year you are only masking other problems withen you pond.
You said you've been making water changes in order to try to clear things up? How big are these water changes? Have you also been cleaning the filter extra as well? I'm wondering if with large water changes and cleaning the filter too often you could set your bio filter back by knocking out to much of the good bacteria? This is just a thought. What I like is to have more filtration than is needed, or should I say what the experts recomend. I have double the amount of filtration for my pond this way when I clean my filteration I know that I'm safe. If I totally kill one filter I have the other set of bio media to back me up.
I am guessing that your pond is in full sun? Or gets a lot of sun. Algae does great in sun. Shade will help a lot.
Benificial bacteria will also help, I use microbe lift but there are many other products out there that do the same thing. It's healthy for the pond and makes it closer to a more natural pond than it is.
Another thing that will help is koi clay. It's not that expensive (especially on ebay) and has many benifits. One though is getting the pond clear, it's also good for the digestive system of your fish and it is good for the plants if you have those. It puts good minerals back in the water that have been used up, these are benificial to the fish health. Thus it also helps bring your pond closer to a more natural habitat for the fish.

Scott

Hello, I have a 125 gallon tank and I use the 36W Turbo Twist sterilizer. A 9W is not big enough to use on a 100 gallon,pond or tank. The higher the watts the better. I use a Magnum 350 water pump with my UV and it works great. UV's are just like tanks, the bigger the better!!

Info on UV Lite.

I have one from them. Works great!

http://www.emperoraquatics.com/uvdetective-comparison.php

You need to get one for a pond, not a Aquarium. There's several different types, generally they hook up in line or you can buy a uv bio filter set up.

Hi, all,
I want to thank you all for your replies, they have been of so much help! That link you gave me, pondandfish, is awesome, and I really enjoyed reading it. I think now, that I know I need a pump vs. a powerhead, and that I should go for as much wattage as I can afford. And Scott, I do let my testing solutions stand for the five minute period, so I'm good to go there. Your reply was just amazing and I thank you so much for taking the time to give me all that info. I have a bio-filter with the balls in it and also a charcoal pad, but my husband installled it and threw away the box, so I don't know what brand it is. I do know that we got it at Lowe's if that's any help. I'll have to check with him about the size of the pump we have, as I'm not sure about that either. I never thought about matching the pump power to the sterilizer. I'll try to get some Koi clay and put that in my pond, too. As far as water changes, I add about 3 inches every other day and have done one 50% change, of which I am planning on doing again today. I have a couple of pond lilies, two black Iris, a horsetail, and two other blooming plants that I forget the name of, in the pond, so I don't know if that's enough or not. Is there a certain amount of plants that should be put in a pond? As far as the pump and sterilizer go, how do I match the pump volume with the sterilizer wattage? Once again, thanks so much to everyone that answered my post, I so appreciate it.
Lynn

Lynn-

It sounds like you have a great set up. I was hoping that you had bio balls in your filter as they generally hold the most good bacteria. With that many plants they would be competing well with the algae for the nitrates in your pond. Hopefully soon your algae bloom will be over.

On the site that pondandfish posted they gave comparisons on water flow with uv lights.

Green = UV Water Flow Rate based On 80% UV Transmissibility, UV Lamp Specifications, and Exposure Area
Red = The Manufacturer's Suggested UV Water Flow Recommendations





notice on the graph it is comparing GPH (gallons per hour) not pond size. When looking at the UV lights you want to make sure that your pump doesn't have a larger GPH than the UV light. It's better to have a bigger GPH with the UV light.

Green Water Flow Rates


You'll need to find out the gallons per hour for your pump.

Scott

Thanks, Kathy, I appreciate the reply and the info

Lynn,

I have to say that I haven't totally been sold on UV lights, that's why I gave other suggestions with the microbe lift and koi clay (which are both great and I do use). Every year since I've had my pond I've had pea soup water in the spring. It doesn't matter what I'd done, this time of year was horrible. But the pond always cleared up nicely for summer, a few spells of cloudy water each month but really not too bad. This year (thus far) my water has been perfectly clear 90% of the time with a few days of light haze in the water. It is unbelievable. My pond is close to 5 ft. deep but the water is so clear you can see every detail of every wrinkle perfectly in the bottom. It only looks maybe a couple feet deep at the most. My UV was too expensive, and I'm not totally sold on it yet. But this is the first spring with it and if things stay the same I'll be convinced that they are worth it. But the bulb replacements are a little over 100 dollars and they last for ONE YEAR!


Scott

UV's dont have to run all the time though, use accordingly. Waterchanges it should be run to kill out any new seed/spores. I don't run it at all in winter, thus effectivly saving wear and tear on the light while still keeping the pea soup gone........