quartz and most plastics are transparent to UV. Ingrid

If so then the tube is very cheap. Tap Plastics has 1" dia x 1/16" wall
six foot long tubes for $4.30

In good units, the most costly part is the quartz sleeve, about 2x the
light.

See above. A brief web search finds a 40w UV bulb for $50. A little
PVC and epoxy, and a ballast from the DH's desk lamp and off you go...

The same site (pondbiz, just the first one I found) has an assembled 40w UV for
$253

Good point. As I recall, the Koi USA one used a plexiglas tube. Dunno if
thats cheaper or not, or how transparent to UV it is...

"Andrew Burgess" wrote in message
...
snip
See above. A brief web search finds a 40w UV bulb for $50. A little
PVC and epoxy, and a ballast from the DH's desk lamp and off you go...
snip

And for those of you with limited knowledge of 'lectricity like me...be sure
you seal the juice from the pond water. Let's now read about a fried
ponder...at least not from a DIY submergible 'lectric device.

BV.

In article ,
Andrew Burgess wrote:

quartz and most plastics are transparent to UV. Ingrid

If so then the tube is very cheap. Tap Plastics has 1" dia x 1/16" wall
six foot long tubes for $4.30

In good units, the most costly part is the quartz sleeve, about 2x the
light.

See above. A brief web search finds a 40w UV bulb for $50. A little
PVC and epoxy, and a ballast from the DH's desk lamp and off you go...

The same site (pondbiz, just the first one I found) has an assembled 40w UV
for
$253

Good point. As I recall, the Koi USA one used a plexiglas tube. Dunno if
thats cheaper or not, or how transparent to UV it is...


I try put ALL UVs on a skimmer line, and DIY type UVs would be best if
they were definitely on a skimmer line, as opposed to a bottom drain
line.

They can leak!

jay
Thu, Jun 12, 2003


--

Legend insists that as he finished his abject...
Galileo muttered under his breath: "Nevertheless, it does move."

"BenignVanilla" m
wrote:

"Andrew Burgess" wrote in message
...
snip
See above. A brief web search finds a 40w UV bulb for $50. A little
PVC and epoxy, and a ballast from the DH's desk lamp and off you go...
snip

And for those of you with limited knowledge of 'lectricity like me...be sure
you seal the juice from the pond water. Let's now read about a fried
ponder...at least not from a DIY submergible 'lectric device.

Lets not forget shielding people, and other animals from the UV.
Doesn't much but a short peek to sunburn your retina!

"John Hines" wrote in message
...
"BenignVanilla" m
wrote:

"Andrew Burgess" wrote in message
...
snip
See above. A brief web search finds a 40w UV bulb for $50. A little
PVC and epoxy, and a ballast from the DH's desk lamp and off you go...
snip

And for those of you with limited knowledge of 'lectricity like me...be
sure
you seal the juice from the pond water. Let's now read about a fried
ponder...at least not from a DIY submergible 'lectric device.

Lets not forget shielding people, and other animals from the UV.
Doesn't much but a short peek to sunburn your retina!

Yes, true. True! I might even be so bold as to sat maybe we should have a
self-inflicted moratorium on recommending DIY UV. There are too many
gotcha's that can gitya.

BV.

Many plastics are very susceptible to UV. Polyethylene becomes brittle, PVC
has UV inhibitors, like carbon black or titanium to prevent degradation, so
depending on the type of plastic, it could be seriously affected and split
or crack, allowing water to the bulb and the electrical connections.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html


"Andrew Burgess" wrote in message
...
quartz and most plastics are transparent to UV. Ingrid

If so then the tube is very cheap. Tap Plastics has 1" dia x 1/16" wall
six foot long tubes for $4.30

In good units, the most costly part is the quartz sleeve, about 2x the
light.

See above. A brief web search finds a 40w UV bulb for $50. A little
PVC and epoxy, and a ballast from the DH's desk lamp and off you go...

The same site (pondbiz, just the first one I found) has an assembled 40w
UV for
$253

Good point. As I recall, the Koi USA one used a plexiglas tube. Dunno if
thats cheaper or not, or how transparent to UV it is...

"RichToyBox" writes:

Many plastics are very susceptible to UV. Polyethylene becomes brittle, PVC
has UV inhibitors, like carbon black or titanium to prevent degradation, so
depending on the type of plastic, it could be seriously affected and split
or crack, allowing water to the bulb and the electrical connections.

Plexiglas isn't degraded by UV, it's used in roof panels.
Good thought though.