I recently installed a 40 watt UV light on my 4000 gallon pond that was
pretty green. You could see down maybe a foot. Each day after installing you
could see down another 6". After a week the pond is crystal clear down to
the 5' bottom. I never really knew if these things would work or not, but
now I am a believer.

Question,

Do they really work well for everyone else? I usually have pea soup in the
spring only and wondered if this would work. If I only ran it in the spring
for a couple of months would I have to still change the bulb out every year?
What is the wattage range to figure electricity costs?

"Mike" wrote in message
om...
I recently installed a 40 watt UV light on my 4000 gallon pond that was
pretty green. You could see down maybe a foot. Each day after installing
you
could see down another 6". After a week the pond is crystal clear down to
the 5' bottom. I never really knew if these things would work or not, but
now I am a believer.

I love mine. I live in zone 5. i also use a filter, and veggie filter. I
wouldnt give mine up for anything. I dont notice a difference in electric, but
mine is small. Lou Ann

"Mike" wrote in message
. com...
I recently installed a 40 watt UV light on my 4000 gallon pond that was
pretty green. You could see down maybe a foot. Each day after installing
you
could see down another 6". After a week the pond is crystal clear down to
the 5' bottom. I never really knew if these things would work or not, but
now I am a believer.

"Ted" sez:
Question,

Do they really work well for everyone else? I usually have pea soup in the
spring only and wondered if this would work. If I only ran it in the spring
for a couple of months would I have to still change the bulb out every year?
What is the wattage range to figure electricity costs?

Works for me well. You shouldn't need to change the bulb frequently if
generally running it only a few months; the bulbs last about a year of
24-hour use due to phosphorescent burn-off, which only happens under power.

Mine is 15watts I think. At our local power cost of 8.9 cents/kWh (which
is recently raised from about 5 cents less than two years ago), it's still
under one dollar per month of 24-hour usage.

I have the "AquaFrog", which was very unknown when I got it but now is
widely carried. It sure simplified plumbing! g You can see it in the
fourth-from-bottom photo at...
http://www.fringeweb.com/Ponds/kc/MyPond.html

Sounds attractive to me.
However, as the features of a unit increase, so does the cost.
Do I need a wiper or quartz sleeve?
Should I use more wattage that I need?
Are there features or brand names that I should look for or avoid?

Doug
..


"Mike" wrote in message
om...
I recently installed a 40 watt UV light on my 4000 gallon pond that was
pretty green. You could see down maybe a foot. Each day after installing
you
could see down another 6". After a week the pond is crystal clear down to
the 5' bottom. I never really knew if these things would work or not, but
now I am a believer.

On Wed, 16 Apr 2003 04:17:25 GMT, "J. Douglas Mercer"
wrote:
Sounds attractive to me.
However, as the features of a unit increase, so does the cost.
Do I need a wiper or quartz sleeve?
Should I use more wattage that I need?
Are there features or brand names that I should look for or avoid?

Doug

I would recommend the wiper option. It lets you safely and quickly
clean the outside of the quartz tube. If it becomes coated with dirt
then the UV output diminishes making the whole thing pointless, but
it's not a must.

The lamp is held inside of a quartz sleeve. This keeps the water from
touching the lamp and shorting it out. Quartz is used because it
transmits UV well, while glass does not. Quartz, although it looks
just like glass, is more fragile. This explains why you often see
replacement quartz sleeves sold on the same web page as the lamps!
You just want to be very careful handling the sleeve.

I would check the various manufacturer's web sites for their
recommended size for your size pond, and then DON'T go with the
smallest/cheapest one - they're just trying to make a sale. The only
time I've heard of anyone being unhappy with the performance of
their UV is when they bought one that was obviously too small for
their pond.

Aqua Ultraviolet is one of the top brands.

Steve J. Noll | Ventura California (zone 10)
| Glass Block Pond http://www.kissingfrogs.tv

"J. Douglas Mercer" sez:
Sounds attractive to me.
However, as the features of a unit increase, so does the cost.
Do I need a wiper or quartz sleeve?

Need? No. You may have to disassemble the unit to clean it sometimes if
you don't get the wiper. I didn't get a wiper, used my unit for about four
months, and it's still sparkling clean, so a wiper would not have yet made
any difference for me.

Should I use more wattage that I need?

It doesn't harm anything to use more watts. I'm actually using less, a LOT
less, than some suggest, with great results. But keep in mind that wattage
is relative to reflection, pond volume, unit volume, water flow, etc. If
you buy a unit with a reflective (aluminum) interior barrel, less wattage
will have the same impact. Slower water flow through the unit gives the UV
more time to act.

Also remember there are two different sets of goals. If you want to
disinfect the water (sort-of), high wattage works. If you merely want to
remove the floating algae and have clear water, a much lower wattage will
still work.

Are there features or brand names that I should look for or avoid?

The biggest factor to me is plumbing. Remember that if you're running it
inline on a filter or waterfall, adding the UV does increase your dynamic
head... so you'd want one with large fittings and a high flow rating. In
my case, I didn't want to splice that plumbing anyhow, and I have a
secondary pump/filter unit, an in-pond box, that I diverted the output
through a UV AquaFrog for; that's an option too.