Aquatic Eco has a TechFact on UV and it shows that the amount of UV in
microwattssec/cm2 to kill algae is sufficient to kill just about everything
except molds, fungi, and higher order critters. For sterilization, to
occur, though, you have to have the water flow through the uv unit at a
frequency faster than the reproductive rate of what you are trying to kill.
For algae, it helps us kill it, since it really doesn't multiply during the
dark hours, and relatively speaking it is a slow multiplier anyhow.
--
RichToyBox
http://www.geocities.com/richtoybox/pondintro.html


"Andrew Burgess" wrote in message
...
writes:

not really. needs a lot of UV to kill critters, a size most people dont
use on their
ponds.

This seems unlikely to be true for bacteria and virus, maybe for larger
parasites.

Kill, damage, slow down or just **** them off, its a positive effect ;-)

not to mention most of the cooties are found on and in the fish

All the parasites I can think of have a free swimming stage.

or the fish
poops or adhering to plants.

Fish poops in my pond are sucked into the filter, clear water out
of the filter goes through the UV.

Kills parasites, bacteria and viruses too.

I've never had to treat for disease or parasites, have plenty of wild
birds
introducing them and have always had UV. This isn't proof of anything but
still, I cringe when I see people post about dosing with antibiotics every
spring...