"BenignVanilla" wrote in message
...

My only aquarium problem is algae on the glass. If someone could solve
that.
I'd be overjoyed.

Heck, I was happy when I got my algae to turn a pretty and healthy green
instead of icky brownish.

AngrieWoman

no, actually, UV is rapidly absorbed by water molecules. few people have gin clear
water which has the highest transmission to UV. A spectrophotometer is probably one
of the only ways to show how many "particulates" and colored soluble molecules there
are in pond water. The other is a disk that is lowered into the water and there are
numbers and it shows how turbid the water is.. I think aquatic ecosystems has some of
these. this is a really crude measure of course, a spectrophotometer is accurate.
Ingrid

Andrew Burgess wrote:

writes:

I am a microbiologist meaning I learned it all a while ago for an exam, but at least
I can still read the literature. In all the sites dealing with using UV to kill
microbes in water (with big sucker units) they specifically talk about how
particulates in the water render the sterilizing ability ineffective. Not muddy
water, particulates.

This just violates common sense. Picture the path of the UV photon
in the water. It either hits a microbe, hits a particle or passes right through, right?
Opaque muddy water, odds are it will hit a particle.

Go read the site and see what the particulate concentration is. Its just common
sense.



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
List Manager: Puregold Goldfish List
http://puregold.aquaria.net/
www.drsolo.com
Solve the problem, dont waste energy finding who's to blame
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Unfortunately, I receive no money, gifts, discounts or other
compensation for all the damn work I do, nor for any of the
endorsements or recommendations I make.

Lee,

I beg to differ strongly.

UV sterilizers measure its light output in microwatts and the amount of
light needed
it measured in microwatts/sec/cm squared. Bacillus megatherium requires only
2,500 microwatts/sec/cm2, while most other bacteria are in the 5-10,000
range. Some require more than this and require 26,400 microwatts/sec/cm2
like Sarcina lutea. Many yeasts are in the 13,000-17,000 range and
then you have mold spores that in the 22,000-99,000 range with Aspergillus
niger requiring 330,000 microwatts/sec/cm2. The Tobacco mosaic virus
requires 440,000 and then protozoa require anywhere from 22,000 to 200,000
and
most Fungi need at least 45,000.

That being said, it should be noted that only about 2% of bacteria require
higher exposure to be killed by UV than algae.

Algae requires 22,000 micro-watt-seconds/square centimeter to be killed and
except for a few exceptions most bacteria is killed by less exposure. E.
coli for example requires only 6,600 micro-watt-second/squared centimeter.
So if the UV you have is working to kill the algae floating around in the
water it is certainly killing any bacteria that requires less than 22,000
micro-watts-seconds/squared cm.

Before the Soviet Unions fall that government was using UV to kill
Salmonella bacteria inside the egg through the shells via massive exposure
to UV.

Granted, gph of water flow, which fixes the time the organism is exposed to
the UV, decides the effectiveness of the killing capability of the device
you own as does turbidity of the water, but all in all UV is one of the most
effective devices found to kill bacteria. And if it is killing algae it is
killing bacteria, especially if it is left running after the algae has
cleared from the water.

Below, is listed the Minimum Lethal Dose (MLD) needed to kill the organisms
listed. I have tried to make the list narrow enough so it will fit into
most email programs.

ORGANISM . . . . . . . . . . MICRO-WATT/SEC/CM2
GROUP One - Bacteria
Bacillus anthracis...........................8,700
Bacillus megatherium sp (vetg) ...2,500
Bacillus megatherium (spores).....5,200
Bacillus paratyphosus....................6,100
Bacillus subtilis (mixed)...............11,000
Bacillus subtilis (spores)..............22,000
Clostridium tetami.........................22,000
Corynebacterium, Dephtheriae.....6,500
Dysentery bacilli..............................4,200
Esberthella typhosa........................4,100
Esherichia coli.................................6,600
Micrococcus candidus..................12,300
Micrococcus piltonensis...............15,000
Micrococcus sphaeroides............15,400
Mycobacterium tuberculosis.........10,000
Neisseria catarrhalis........................8,500
Phytomonas tumefaciens................8,500
Proteus vulgaris................................6,600
Pseudomonas aerugenosa...........10,500
Pseudomonas fluorescens...............6,600
Salmonella sp..................................10,000
Salmonella enteritidis........................7,600
Salmonella typhimurium (ave).........15,200
Sarcina lutea.....................................26,400
Serratia marcescens..........................6,160
Shigilla paradysenteriae....................3,400
Spirillum rubsum..................................6,160
Staphylococcus albus.........................5,700
Staphylococcus aureus.......................6,600
Staphylococcus lactis..........................8,800

GROUP Two - Yeasts
Saccharomyces ellipsoideus...........13,200
Saccharomyces sp............................17,600
Saccharomyces cerevisiae..............13,200
Brewers yeast......................................6,600
Bakers yeast........................................8,800
Common yeast cake.........................13,200

GROUP Three - Mold Spores
Penicillium roqueforti.........................26,400
Penicillium expansum........................22,000
Penicillium digitatum..........................88,000
Aspergillus glaucus............................88,000
Aspergillus flavus................................99,000
Aspergillus niger...............................330,000
Rhisopus nigricans...........................220,000
Mucor racemosus A............................35,200
Mucor racemosus B............................35,200
Oospora lactis.....................................11,000

GROUP IV - Virus
Bacteriophage (E. Coli)........................6,600
Tobacco Mosaic................................440,000
Influenza......................................... ..........6,800

GROUP V - Protozoa
Paramecium.......................................2 00,000
Nematode eggs....................................92,000
Chiorella vugaris (algae)......................22,000
Trichodina sp.........................................35,500
Trichodina niger..................................159,000
Saprolegnia sp..(zoospore).................35,000
Saprolegnia sp..(hypha).......................10,000
Sarcina lutea..........................................26, 400
Icthyophthirius sp. (tomite)..................336,000
Icthyophthirius sp. (tomite)..................100,000
Chilodonella cyprini...........................1,008,400

GROUP VI - Fungi
Fungi............................................. ...........45,000

HTH

Tom L.L.
--------------------------------------------
"Lee Brouillet" wrote in message
...
UV's will kill single cell algae, the ones responsible for "green water".
MOST UV's, and I make that statement with confidence - do NOT kill
bacteria.
The wattage necessary, and the dwell time of the water while exposed to
the
light, just isn't within the reach of most of us. Like a lot of equipment
aimed at ponders, the capabilities of a UV are very overstated. That being
said, the UV can *only* kill that which passes through it. The biobugs
growing in the biofilm growing in your filters is static: it doesn't move,
is not exposed to the UV, and is not subject to annihalation by it. Want
to
kill green algae? Get a UV. Want to kill string algae, bacteria, etc.?
Find
something else.

Lee


"FBCS" wrote in message
...
Man from Skippy filter (maybe Skippy, I don't know) say to get rid of my
UV
if I use his filter. Can someone expound on this?

writes:

no, actually, UV is rapidly absorbed by water molecules.

Rapidly? Got any numbers? UV purifiers look like they have an inch
or two of water for the UV to pass through. Can we agree its probably not
significant in the first two inches?

few people have gin clear
water which has the highest transmission to UV.

Of course the clearer the better the transmission.

A spectrophotometer is probably one
of the only ways to show how many "particulates" and colored soluble molecules there
are in pond water. The other is a disk that is lowered into the water and there are
numbers and it shows how turbid the water is.. I think aquatic ecosystems has some of
these. this is a really crude measure of course, a spectrophotometer is accurate.

So?

"Tom La Bron" writes:

UV sterilizers measure its light output in microwatts and the amount of
light needed
it measured in microwatts/sec/cm squared. Bacillus megatherium requires only
2,500 microwatts/sec/cm2, while most other bacteria are in the 5-10,000
....

Ah numbers. Thank you thank you thank you.

Andrew,

To correct something that "Ingrid the microbiologist," said, and she has
said this before and I can't understand why she keeps saying it, but she
says that "the UV roughs up the cell walls making algae clot and sending it
to the filter or to the bottom," which is a bunch of horse manure. The
germicidal effects of UV light involves photochemical damage to the DNA and
RNA within the cells of the organism. The Nucleic acids of the cells
actually are absorbers of the UV radiation and thusly the UV damages this
part of the cell inactivating it. Golly, you would think a "microbiologist"
would know that, instead of saying that the UV roughs up the cell wall to
make it clump, and if you don't believe me this information gleaned from
Paul Hundley with 25 years of experience and tons of degrees, who deals with
this stuff off the time in the aquaculture community.

Oh, while I am at it, turbidity is important, but if the UV sterilizers
didn't work on algae (actually a pretty large organism) and clear up algae
blooms, what Ingrid and Lee are saying it won't work on algae bloom, but it
does. The reason for this, for those who haven't thought about it, is that
the circumference of the tube that the UV light goes into is usually pretty
small and with the space literally taken up by the UV light it self, the
volume of area where the water flows through is actually relatively small
compared to the entire pond. Now, of course, the UV doesn't kill all the
algae as it passes through the tube, but it kills some and eventually kills
it all.

No manufacturer is touting one time pass killing of organisms when they are
talking about pond sterilizers, they are counting on the chance of
multiple-passes of water through the UV to get all the algae.

In public water systems that is not the case. They get one chance to
sterilize the water as it passes through on to the consumer thus requiring
megadose UV units.

Come people we are talking about recirc pond systems here not public demand
systems. Some of you are talking Apples and Oranges. Get is grip.

Ingrid also eluded to the size of the organism, I would just like to repeat
for those that didn't catch it in my message with killing capacity of UV
that algae is a big organism compared to most bacteria, so if it is killing
algae it will kill the bacteria also, especially if you leave the UV running
all the time, eventually it will pass close enough to be killed.

HTH

Tom L.L.
----------------------------------------
"Andrew Burgess" wrote in message
...
"Tom La Bron" writes:

UV sterilizers measure its light output in microwatts and the amount of
light needed
it measured in microwatts/sec/cm squared. Bacillus megatherium requires
only
2,500 microwatts/sec/cm2, while most other bacteria are in the 5-10,000
...

Ah numbers. Thank you thank you thank you.

Correct, UV sterilizers are designed to have a short path of a cm or less.
Spectrophotomers are designed to measure particulates that cannot be seen with the
naked eye. What appears to be "clear water" can actually be full of particulates.
OK. I have a 25 watt UV. p. 334-335 aquatic ecosystem cat.
One of their 25 watt models is rated for 15,000 mws at 12.6 gallons per minute.
Killing algae requires 22,000 mws so gotta slow the flow to 8.6 gallons per minute.
My maxi 1000 runs at 230 gph or 3.8 gallons per minute.
Aquatic Eco recommends the entire volume of the pond goes thru the UV 4 times per 24
hours.
My pond is 1800 gallons, at 230 gallons per hour it takes 7.8 hours for 1X, so only
get 3X+ per 24 hours.
-----------------------------
my UV had been used at least 1 year before somebody gave it to me. I have now been
using it for 4 years without changing the bulb. After 6 months the efficiency can
fall 40%, so each 6 months sees a 40% drop off... and after 5 years that means 10
"half lives" (60% after 6 months, 36% 1 year, 12.9%- 2 years, 4.66%-3 years, 1.67%-4
years, etc.)
So even being generous that the efficiency could still be 10%, that means to get
22,000 mws it has to be 1/10 the flow rate or 0.86 gallons per minute, but mine runs
at 3.8 gallons per minute or 4.4 times too fast to attain 22,000 mws. so now I am
only getting 5,000 mws at 3.8 gpm. This is way below killing for algae. We wont
count the particulates in my pond, nor the yellow coloring as my water is not gin
clear. Both these affect kill and AES recommends getting UV lights 40% over what is
minimum.
So all of this is very interesting cause this spring I had pea soup, cranked up the
UV and in 4 days the pea soup was gone.
--------------------------
what I did observe is that algae that had been flowing wild and free thru my filter
for some reason ended up sliming my filter after I cranked the UV up. Now UV creates
cross links in the DNA of cells. So if the only change to the algae was inactivating
the DNA it should flow thru the filter just the same as before gradually
disintegrating, not load my filters up with green gunk.
So what I got here is a bona fide miracle, cause there is no way that old UV is
"killing" my algae... not according to the "specs". And it is one reason I tell
people to save their money, dont change their UV bulbs until pea soup returns.
Ingrid

Andrew Burgess wrote:
UV purifiers look like they have an inch
or two of water for the UV to pass through. Can we agree its probably not
significant in the first two inches?

few people have gin clear
water which has the highest transmission to UV.

Of course the clearer the better the transmission.

A spectrophotometer is probably one
of the only ways to show how many "particulates" and colored soluble molecules there
are in pond water. The other is a disk that is lowered into the water and there are
numbers and it shows how turbid the water is.. I think aquatic ecosystems has some of
these. this is a really crude measure of course, a spectrophotometer is accurate.

So?



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
List Manager: Puregold Goldfish List
http://puregold.aquaria.net/
www.drsolo.com
Solve the problem, dont waste energy finding who's to blame
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Unfortunately, I receive no money, gifts, discounts or other
compensation for all the damn work I do, nor for any of the
endorsements or recommendations I make.