The contemporary ground-swell of allegiance
to herbal medicine was bound to have effects
in fishkeeping. Did it begin with the use
of aloe vera extracts as an all-purpose balm for fish, which originated
in the Great Aloe Vera Fad of the 1980s?
Does it have spiritual links to aromatherapy?
Or did Jack Wattley start it with his garlic
cure for hexamita in Discus?
A trendy industry is building round the use
of extracts derived from several species
of Melaleuca. Pleasantly fragrant M. alternifolia, or Tea Tree, oils have been perfuming hair-care
products for thirty years.
To get the mildly
zany flavor of it all,
run "Melaleuca"
through your favorite search
engine.
There is a long list of claimed curative
properties of Melaleuca oil reported in various
journals at www.thursdayplantation.com though many accounts concern topical application
of the essential oil itself, not a 1% solution
dispersed in the volume of water of your
aquarium. For instance, there is a sober
report of Tea Tree oil effectively used to
treat symptoms of skin troubles in dogs and
cats at www.alternativemedicine.com
A Melaleuca product won a citation for "best
new product" in 1999 from the Pet Industry
Distributors Association, who are as well-positioned
as anyone to detect a smart marketing move.
The manufacturers gained a U.S. patent, based
on their process for rendering the oil-based
Melaleuca extract water-soluble, with an
emulsifier. Not an easy trick. The result
foamed up so much though, that a Dow-Corning
anti-foaming agent had to be added to the
brew. The Melaleuca species in question is
not M alternifolia, but Vietnamese "cajeput," Melaleuca cajuputi and M. leucadendron, according to the patent specifications,
which were tracked down by a member of www.AquaBotanic.com
and posted 30 March 2003. Aquarium strength
is 1% cajeput oil, pond strength is 5%. The
manufacturers claim that their product "also
caused rapid repair of damaged fish tissue
and fins. New growth was seen in as little
as four days of treatment. This evidence
led to the granting of a United States patent."
Everyone should be well aware that U.S. patents
are not granted on the basis of any claims
of efficacy, whether proved or unproved. http://www.aquariumpharm.com/techref/aquarium/apb11.htm
Whether or not concentrated
Melaleuca extracts
have all the properties
claimed for them,
Doc Johnson at KoiVet reports enhanced healing of body sores in
koi treated with Melaleuca
extracts.
Other herbal "protections" exist.
Fish exporters in Singapore, for example,
add a dry leaf of the Ketapang tree to the
water in each shipping bag, and they feel
that the leaf cuts losses during shipping.
(I'm getting this from a semi-official Singapore
University web site http://www.dbs.nus.edu.sg/fish.) The Ketapang tree, Terminalia catappa, the "Sea Almond", is a member of the tropical mangrove coastal
ecosystem. Tannins and black dye are extracted
from dried leaves and other plant parts.
The plant has many traditional medicinal
uses, treating dysentery and even leprosy
(which is a mycobacterial disease). The tree
occurs naturally over extensive areas of
tropical southeast Asia, as far as northern
Australia and some western Pacific islands.
Ketapang has become even more widely planted
throughout the Old World and the New as a
tropical shade tree, so its leaves are reassuringly
familiar and conveniently at hand to the
fish farmers of Singapore. Most of the Terminalia species (of which there are perhaps 200)
are chemically rather active. They produce
gums and resins, dyes, and tanning extracts.
Lethal concoctions can be brewed from the
roots of an African species of Terminalia,
and contact with the sawdust of some Terminalia
timbers have produced rashes. Some others
produce arthroquinones, my quick check reveals.
So it's not impossible that there is some
genuine bacteriostatic effect produced by
Melaleuca extracts or a Ketapang leaf placed
in shipping water. All to the good, then,
if you feel that bacteria exist to be eliminated!
Plants produce a wide range of allelochemicals,
necessary to protect them from constant degradation
by every fungal spore or bacteria that passes
by. These alkaloids and terpenes (and phenols
in aquatic plants) have often been demonstrated
to be mild but rather non-specific inhibitors
of bacteria. Diana Walstad, who reports these
conclusions, adds, "The allelochemicals
responsible for the inhibition were identified
as tannic acid, gallic acid [that's another
humic substance] and ethyl gallate, all common
phenolics found in many aquatic plants."
(Ecology of the Planted Aquarium, 1999, p. 44.) So there's no reason not to
suppose that Melaleuca alternifolia is similarly protected.
Still, the chemical identification of the
pharmacologically-active ingredient in a
leaf or bark does require some pretty intensive
laboratory detective work. That can be expensive,
too. Sensibly, the enthusiasts of herbal
medicine commonly sidestep any specific identification,
relying in preference on a holistic synergy
of all the unrefined "natural"
ingredients acting together. So, when a stricken
fish has pulled itself together, it's hard
to disprove the efficacy of this or that
herbal tea. And mean-spirited too, I warrant.
You can imagine that I detect unskeptical
faddism whenever I hear wide-ranging properties
ascribed to whatever plant that's in current
favor. At the very least, be wary!
As for me, I try to keep an open mind about
all this, but you can tell I'm just not very
sympathetic. You see, commonplace Garden
Sage, Salvia officinalis, has bacteriostatic qualities too. So I
might brew some sage leaves overnight and
add the liquor to the tanks, if I were of
a mind to kill some bacteria at random...
or maybe some cold-brewed Sleepytime Tea.
Or St-John's Wort for the tetras: that might cheer them up.
