RAINWATER A COMPLEX
By Jim E. Quarles
So you're thinking about using rainwater in your discus tank right?
Well it is nice and soft, but just what's in it?
According to the most recent report by the National Water-Quality
Assessment Agency, after samples were taken at sixty five randomly
selected sites across the United States with a least one sample in each
state, the following was found to be in the rain water of most regions
tested in at least trace amounts.
Trace amounts to heavy
Aluminum, Antimony, Arsenic, Barium, Beryllium, Boron, Cadmium,
Chromium, Cobalt, Copper, Iron, Lead, Lithium, Manganese, Mercury,
Molybdenum, Nickel, Radium 224, Radium 226, Radium 228, Radon 222,
Selenium, Silver, Strontium, Thallium, Uranium, Vanadium, Zinc, Gross
Alpha-radioactivity, Gross beta radioactivity.
I ask you, does the above sound like something you would like to add to
your discus tanks??
In addition to the Rainwater tests the NAWQA also tested stream bed
sediments in the same areas and for a distance of up to fifty miles from
the rainwater collection points.
The same elements were found concentrated in a higher percentages then
would have normally have been expected.
Then they tested the tissues of fish and clams in those waters.
Basically the same elements were found in these tissues with the exception
of Radium 224, Radium 226, Radium 228, Radon 222 and no trace of Gross
alpha-radioactivity or beta-radioactivity. Also missing was Lithium, the
absence of these items can be explained in their chemical or radioactive
Acid rain is reported to be killing trees and forests hundreds of miles
from the major source of pollution. There are reported cases of fish being
killed in lakes due to acids contained in rainwater.
CAN RAINWATER BE MADE SAFE FOR
Of course it can be made safe for aquarium use, but at what cost? And
how would you take the required steps or buy the right equipment to
provide this task?
Before talking about what is required to remove the heavy metals from
rainwater perhaps it should be pointed out that in the tests performed in
this study pesticides & herbicides were not even considered nor were
the tests design to detect any that were present.
I would venture the statement that rainwater as collected in most
locations such as medium to large cities is not fit in its natural state
to be used in the culturing of fish of any type.
Dr. Schmidt-Focke told me one time about how he used to collect rain
water behind his house in Germany. But he had to start transporting his
water from a fairly great distance because the rain in Germany had become
so laden with heavy metals and pesticides it was no longer fit to use in
his tanks. I am sure this is even more of a problem in the United States
With few exceptions all the major hobbyists keeping discus now days use
either R.O. units or water treating Resins to remove heavy metals and
other undesirable elements from their water supplies.
If you were to design a system to pump your collected rainwater through
a R.O. unit or Resin unit I am sure the water would then be acceptable for
discus breeding. But then if you avail yourself of such a unit you would
be able to use your normally supplied tap water and have no need to
collect and store rain water.
I hope this answers the simple question, can you use collected rain
Yes of course you can. Is it good water for discus? I think not. I
would not advise it. Of course you can collect samples and have them
analyzed in your area to find out for sure. This can be expensive but if
you plan on using the water it perhaps would be a good investment.