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[APD] RE: copper (long)

>From: "Thomas Barr" <tcbiii at earthlink_net>
& R=866&N=2004+113521
>This will give you some estimation of how much you'll need for effective
>dosing without worry about toxic Cu effects on fish. 

I always get a chuckle to see the old topics discussed over.  I checked the
APD archives and couldnt find my original posts from the early years... you
know, when we called the internet the superhighway <g>. I did find this on
my hard drive. I think i put it in TAG around '92-'93. It addresses the
toxicity to fish issue. My earlier article discussed the sensitivity of
different algae to copper. Cladophora and Audouinella (BBA) were listed as
"sensitive." Many bluegreens, flagellates and a few greens  including
spirogyra are listed as VS.

An Update of the Use of Copper (early 90's).
I previously reported on the use of copper as an algicide . Because copper
is toxic to many species of fishes, I recommend that fish be removed prior
to treatment.  However, the sensitivity to fish varies and some seem to be
unaffected by concentrations used in the copper treatment. Here are the
results of an ad hoc experiment to examine this issue.

I decided to treat one of my densely planted tanks for the red alga
Audouinella, but was too lazy to remove the fishes. The 55 gallon tank
contained 6 keyhole cichlids, 6 rams, 10 congo tetras, 4 diamond tetras, 6
platys, 1 bristle nose and 8 clown loaches. The plants consisted of
Cryptocoryne affinis, Hygrophila polysperma and Vallisneria spirilus. I
introduced the copper over a 2-day period and observed the behaviour of the
fish. At the first dose of 0.2-0.3 ppm copper, I noticed heavy breathing
among the clown loaches and bristle nose, so they were all removed to
another tank. Once released in the copper free environment, they completely
recovered. All of the remaining fish appeared to behave normally and were
allowed to remain with he copper. I increased the concentration to 0.5 ppm,
and the fish appeared to do OK. I did notice that within the first minute
to so, the keyholes jerked around for a few seconds, but then immediately
calmed down. I was reasonably confident that they would not be adversely
affected, because I had previously exposed other cichlids (Cichlasoma
portalegrense) without ill effects. 

I maintained the copper treatment for 10 days and at the end of the
treatment period, I successfully eradicated the furry red algae. The tetras
and the cichlids all survived without incident, but one half of the platys
had died (within the first week). This illustrates the difference in
sensitivity among fishes, but more importantly, demonstrates that some
fished do not have to be removed for the copper treatment. If I had to
repeat this procedure, I personally would not bother to remove tetras or
cichlids, but would remove livebearers, loaches and catfish.

The plants reponded as expected - the crypts and hygo were fine and the
Vallisneria leaves all melted away.

Since I did not want to remove the fish at this point, I did two successive
75 percent water changes. This removed 87 percent of the remaining copper,
reducing it to a level less than .07 ppm. I decided that this was adequate
and than future periodic water changes would further dilute the residual

Although I had effectively reduced the Audouinella and probably other algae
as well, I had an outbreak of a new algae. Within a few weeks, the tank was
covered with a soft greenish brown variety (type unknown). It covered the
leaves and the glass. I was not entirely surprised, since I had added new
nutrients with the water changes and had tanken away my algae eating fish
(the bristle nose and the platys). I soon corrected the problem by
re-introducing a few bristlenose and Octocinclus. Within days, the algae
were gone and the catfish had full bellies.

The crypts are now busy putting out new runners, the hygo is actively
growing and I have replace the val to complete the aquatic landscape.

After  I wrote my articles on copper. I came across one rather uncommon
reference in the aquarium literature - Know Your Aquarium Plants by Don
Jacobs. This soft cover booklet is undated, but was published by Pet
Library Ltd around 1970. (This is the same book publishedbt TFH in 1986
under the title: The Basic Book of Aquarium Plants).  Jacobs mentions that
"0.5 ppm copper stimulates healthy growth and rich coloration in most
plants like Cryptocoryne, but this same concentration promptly kills
Hornwort (Ceratophyllum), some algae, Vallisneria leaves and many fish
parasites." Jacobs also provides a sensitivity scale for copper:

Ceratophyllum (most sensitive)
Oodinium (Velvet Disease)
Flukes (Gyrodactylus worms)
White Cloud Mountain fish
Ramshorn Snails
Philippine Livebearer Snails
Most other fishes
Many other plants

Philippine Livebearer snails are also known as Malaysian Trumpet snails
(Melanoides sp.). Although copper concentration of 0.5ppm will not kill
them, it does seem to bother them. This concentration of copper will cause
them to literally climb the walls of the aquarium which may help remove
them from a tank.

In conclusion, copper is useful but should be used as a last resort. With
the aid of a test kit and knowledge about sensitivity to plants and
animals, however, aquarists can safely use copper as part of their aquarium

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