UV lights for giardia?
 

Giardia [also known as beaver fever] is a nasty little protozoa that
I'd like to keep from taking up residence in my pond. It is
frequented by 3 pugs & though we can train them not to drink from the
pond- it is a handy source of refreshment for them.

Does anyone know what the strength of the Tetra 5w UV light is? I've
been using one with great success against algae.

I found a chart at
http://www.awwa.org/files/Advocacy/G..._Figure_17.pdf
that tells me how much UV is needed to kill Giardia-- but I don't
understand enough of the terms to understand the chart.

What is a "log credit"?

How do I determine millijoules/cm2 from the flow through my light?

This page says that I need to measure flow rate, UV intensity & UV
Transmittance.
http://www.awwa.org/files/Disinfection.pdf

I looked for a similar chart for killing algae, so I can see if it
takes more or less UV. If I'm reading this one correctly- it takes
much more UV to kill Algae [22000 microwatt-seconds per square
centimeter] than Giardia [10000 microwatt-seconds per square
centimeter]. Any water specialists agree/disagree?
http://www.islandnet.com/~tiger/Tige...w_uv_works.htm

Thanks,
Jim