Fish Q&A Section: All About Copper
Copper Sulfate, Is it safe?
Many people have had a bad experience with, or are afraid to use
Copper Sulfate on their fish because they have been improperly
informed on the mixing, dosing and usage of this product.
First we will tell you what Copper does:
Copper Sulfate is pretty much an all-around treatment. It
is an Algaecide, meaning that it kills Algae, it is Anti-Bacterial,
Anti-Fungal, works on external Protozoa such as Ich, and works on
Oodinium, Sliminess of the skin, and kills certain parasites such as
Cryptocaryon Irritans (Salt water Ich) and Crustacea (Argulus).
It also works as a great preventative treatment for most all fish,
freshwater or saltwater. We used to use it on Gill Flukes
years ago, but now, the Gill Flukes have become resistant to this
How to mix up a Copper Solution properly:
Stock solution= 21 grams of Copper Sulfate + 21 grams of Citric
Acid Crystals to 1 pint of distilled water. Shake well.
Use 1 drop per every gallon of aquarium water= .15ppm. Why use
Citric Acid with Copper? Simple, it sequesters the solution to
make it stable. Copper does not readily dissolve in water.
The Citric Acid helps it to dissolve completely and prevent Copper
levels from bouncing around.
How high can I run Copper?
Safe levels are .15ppm to .20ppm. Any higher may burn the
fish and leave them with red sores on their sides. It is very
important to use a Copper test kit when medicating with this
How do I remove Copper?
A common misconception about Copper is that it can be removed
from the water with activated charcoal. It can only be removed
by either doing water changes, or by using E.D.T.A. (Ethylene
Diamine Tetra Acidic Acid) to chelate it out of the water.
Remember folks, there is no such thing as a "Chelated Copper
Solution", as "Chelated" means "Inactivated". The proper
terminology would be "Sequestered Copper Solution".
Warnings before using Copper:
Although Copper is safe at the correct parts per million, there
are certain things that Copper cannot be use on: Saltwater Sharks,
Invertebrates, and for sure... reef tanks.
Also, be careful if using Copper to kill algae. When you
dose the tank, the Copper readings will disappear, because the algae
will suck it all up. Then the algae dies, and releases all of
the Copper back into the water.
Copper is a heavy metal ion and is
considered a "Poison". Care should be used when handling this