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Quality UV lights for your garden ponds

Vol:  404 Date:

Mar 4th 2004  

The Water Gardens Gazette 

1. New supply of Industrial Quality UV lights

2. Even More Answers. The Nexus ... second article by William Kelly of Happy Koi

3. Admin section

1. New Supply of Industrial Quality UV lights

I first met the owner of the company that manufactures these excellent quality and strong UV units about 6 years ago and he was too busy on other industrial development to worry too much about smaller UV installations for ponds. I am now pleased to announce that he has allowed Focus to distribute these units to those pond keepers with larger pond volumes who really pride themselves on using the best and most efficient units on the market.

Readers of this newsletter will know that I have traditionally only supplied 4 and 8 watts UV units (for ponds of max volume 6,000 litres). The reason was that importing larger units suitable for our conditions with Quartz tubes made the UV lights too expensive on the surface because people did not understand the difference a quartz tube made. The well known locally manufactured units that have been sold for many years did not have Quartz tubes and as such were misleading (in my opinion) as to what the true capacity was.

As a brief reminder if an UV does NOT have a quartz tube installed to prevent direct impact of cooler water on UV lamp then lamp efficiency drops off rapidly (50% only at 20 degrees C water temperature). In practice an UV 0f 30 watts without a quartz tube has the same (approximately) algae killing power as a 15 watts with a quartz tube

Here are salient details of the new units ... they can be made available without Quartz tubes if desired ... and each one is made in South Africa.

Ultra Violet Clarifiers 15 Watts and Larger Units Only 220 and 240 volt systems

Used properly these units guarantee clear water in any pond system. They are the fundamental secret to crystal clear water in koi, gold fish and other fish ponds.

They do the job of removing suspended algae they have no impact upon filter bacteria or blanketweed or other types of algae which are not circulated through the UV unit

The unit can be fitted anywhere in the recirculating system provided that the maximum steady pressure is less than 4 bar. If PRESSURE filters are used it is generally best to fit the UV unit after the filter to optimise internal water clarity. In gravity biofilter situations place the UV before the filter

It is best to connect the UV unit into the pump circuit so that it is always running when the pump is on. If the unit is repeatedly switched on and off you run the risk of fogging up the quartz tube and thereby reducing the efficiency

No units must ever be submerged!

When choosing a UV unit for re-circulating aquatic use, the TOTAL VOLUME OF THE WATER in the system is more important to consider than the flowrate of the pump. This is because the algae can be killed by repeated smaller UV doses, and it not necessary to destroy a very high percentage of algae on each cycle. However, if the pond is very large relative to the UV unit, it will take too long for all the water to re-circulate through the UV unit often enough to be fully effective. In general, faster flow rates are preferable to slow recirculation. So long as the pond volume is turning over about 6 times per day or more then don't worry about this factor too much.

 If an existing pump is providing a greater flow than the UV can handle, and an undue loss of pressure occurs, we recommend the following action: Fit a by-pass to the UV module in such a way that that the main flow is directed into the UV unit. This will ensure the maximum flow through the unit, and allow excess flow to by-pass it. Do not tee the UV unit off an existing straight pipe, or you may find that virtually no water passes through it at all!

 We also suggest that a suitable filter be used. The combination of filters and UV units has been shown to give much better results than either alone. Whenever you keep fish in a pond it is an absolute must that you install a biofilter adequate enough to do the biofiltration job.

Model (NQ means NO quartz tube)

Maximum Pond Volume litres

Wattage

Size in mm

Focus15Q

13,500

15

470*150*260

Focus15NQ

7,000

15

470*150*260

Focus 30Q

27,000

30

930*150*260

Focus 30NQ

15,000

30

930*150*260

Focus 55Q

43,000

55

930*150*260

Focus 55NQ

24,000

55

930*150*260

Focus 75Q

80,000

75

1230*150*260

Focus 75VQ

45,000

75

1230*150*260

Please ring Priscilla of Brenda for prices at 011-454-0105 .. delivery 1 week approx from order date

2. The Nexus and The Answer ... William Kelly's 2nd article

I am not a Koi pond builder or construction expert. I do however know what is needed in a Koi pond and would suggest that if you are serious about keeping large Koi your pond has to be at least 10 000l. Smaller than that please consider keeping goldfish if you don't want to regularly bury Koi. Koi grow too big to be kept confined in smaller environments than 10 000l.

As with all things Koi, bigger is better. Size counts for everything, even with the Koi themselves. Bear this in mind when it comes to selecting your filtration equipment. If you do your homework into the hobby and you do things properly the first time, your Koi will live and prosper and they will grow. This increase in growth places an increased demand on your filtration system. It sounds obvious, but a 40cm Koi 665 grams on average is very different from a 90cm Koi that can weigh 8448 grams on average. That's twelve times the weight of Koi and twelve times more filtration load!

It still amazes me that people still buy biofilters that are 'rated to treat XXX l of pond water'! Such a rating is completely and utterly meaningless. My biggest problem with it is that it is deliberately misleading to the detriment of the purchaser. What if there is only one single fish in this pond? What if there are a hundred? What if these fish are all 10 kg or heavier? What if they're Koi and not goldfish?

The only meaningful rating is one which indicates how many kilograms of Koi fish weight the bio filter is capable of handling, and at what speed (rate) the bio filter is able to breakdown wastes. It's no good if the bio filter takes three days to remove the wastes produced by Koi - no Koi would be very happy at only being fed once every three days! Remember too that Koi on a weight for weight basis produce about twice as much filtration load as goldfish do - Koi are not known as the 'pigs of dams and rivers' without good reason!

My advice is that any bio filter offering a rating based on pond volume is seriously flawed. Stay away. The designers of these so called biofilters have made a guess as to how many fish would be living in such and such a pond volume, and worse, they've guessed how big these fish are. Even worse, if they have made all these guesses, do they in fact know how many milligrams of ammonia the filter is capable of removing per hour at a specified flow rate and under what conditions? My guess is that they have no idea. In modern Koi keeping, this is nothing short of genocide. The one thing that I can promise you is that once your fish load exceeds these guesses, the only certainty is that your local Koi graveyard is going to be doing a lot more business!

There is no substitute for homework when it comes to Koi keeping. It's a lot of fun and tremendously rewarding to see the results in action. Don't be put off, the processes are not that complicated to understand. All it takes is time. Don't be afraid to ask questions and get second opinions.

Do your homework and be rewarded. Fail to do it, and be condemned!

Until next time. For more info visit Happy Koi by clicking here or go to http://www.happykoi.co.za or e-mail me, William Kelly with any questions. Were here to help.

FREE when you buy at the Pond Professor's book store or click here to learn more first    

Recommendations Worth A Look Visit the only Water Gardening Web Store in South Africa Breaking News .... at last 15 watts and 30 and 55 and 75 watts UV units with and without quartz tubes. Just remember if no quartz tube efficiency is ONLY 50% or in other words 15 watts with quartz tube is twice as powerful as 15 watts without quartz tube

Ring Tony for more details 011-454-0105.

Focus Koi Food Special ... 20% off. Ring Brenda or Priscilla at 011-454-0105 and refer to gazette 404 special offer

3. Permission To Publish and Admin section

Bona fide web masters and web site owners who have a genuine interest in helping people succeed in pond keeping are welcome to publish articles from these Gazettes subject to one simple condition. Please include in the opening to the article the following link. All you need do is copy these 2 lines of code and paste into your HTML

"http://www.practical-water-gardens.com/"

All you need to know about water gardens, ponds, pumps, bio filters and UV lights

This code will show as follows on your web page .... All you need to know about water gardens, ponds, pumps, bio filters and UV lights

It is very difficult to find a summary of pond plants. It is even more difficult to find out in a table form what colour (if any) the flower is and whether they like sun or shade. Finding size when fully grown is also a challenge .... so I have done the hard work for you. get it here ....  Click here and be patient ... it is large file

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