- Copper is an element that many of us
in the reef hobby are familiar with.
Atomic number 29, in its pure form
it's a recognizable orange metal,
though I would be surprised
if you might see it like that in your reef tank.
Maybe people add it as a treatment for ich
or another disease in their fish, but you're far more likely
to run into copper compounds in your aquariums.
Those compounds are often invisible in solution,
a tiny amount of copper has a quite a big effect,
but a higher concentration of it
will give it maybe a nice blue greenish kind of color.
Hi guys and girls, I'm ReefMan,
and this video is all about copper.
What is a safe level of copper in your reef tank?
How does copper affect the coral? What makes it so bad?
What test kits are gonna work to test for copper?
Let's dive in and find out!
So what is a safe level of copper?
Well, unless you're using a Triton kit
or another ICP style test on your tank,
there really is no safe level of copper.
Most home test kits are only gonna be testing
in the parts per million,
maybe down into the high parts per billion,
and even one part per million is way too much
for most coral to handle, or really any coral to handle.
If you are using an ICP test kit, though,
then maybe you might get like one or two parts per billion,
and you could watch that with caution,
but really even those tests
should not be detecting any copper.
So if you see any copper at all,
it's likely to be causing issues,
and these issues tend to build up over time.
You should never intentionally add copper to your reef tank.
If you do need to use it to medicate a fish,
or maybe to get rid of ich or something like that,
you have to do the medication in a different tank.
That's a whole different topic though,
so for this video I'll suffice to say
that you should just never add copper,
or anything containing copper, to your reef tank.
Even without coral, copper can slowly leach
out of live rock or anything porous over time,
and so live rock or anything that's porous
that is in a tank with copper
should never be used in another tank with coral.
That's not to say that coral doesn't need any copper at all.
Actually all living things need tiny amounts of copper
just for their normal biological processes.
For instance, copper is important
in the creation of a compound called elastin.
That's the compound that makes your skin and other tissue
stretchy so you can open your fingers.
Coral, Cnidarians, they have elastin as well.
They also have collagen, that's an important protein
found in your body as well
This level of copper is gonna be all but undetectable
in our tanks though, and it really is provided
by the fish and coral food that you're gonna add,
or maybe in your water changes, 'cause your tap water,
even your ROID water, probably has
tiny bits of contamination in it.
So what does copper actually do to coral if you did add it?
Well, in short, it kills it. But how?
To answer this I turned to a research library
where I found a paper published back in 2010
titled "Sub-cellular damage by copper
in the cnidarian Zoanthus robustus".
The paper is linked down below in the description
if you want to check it out.
It's pretty neat, I'd recommend it.
The researchers chose Zoanthids to study
because they're essentially just a bigger version
of the standard coral polyp.
Overall, you can think of Zoanthids as having
the same morphology as those tiny polyps that you see
on your Acropora, but since it's much bigger,
you can see the changes and damage a lot easier.
At a very basic level, excess copper in the water
can be damaging because it helps in the production
of hydroxyl radicals which go on to hurt
all sorts of things inside the coral.
Now cral do have some capacity to rid themselves
of those free radicals, but they can only do so much.
Copper overwhelms that capacity
leading to all sorts of damage
in things like amino acids, even in the DNA itself.
Copper can actually also block the sites that use,
or that coral use to export those compounds,
so even if coral is able to bind up those free radicals
it can't remove them from its tissue.
In a study of Pocillopora coral,
there was actually a retraction of polyps
and a loss of tissue after just 14 days
of exposure to 50 parts per billion copper.
Another coral in a different study was exposed to copper
for 15 days, and then they used a toothbrush
to scrub off some tissue.
The copper exposed corals died while the control corals
which didn't get any exposure to copper recovered.
So looking at the tissue that was actually removed
in that test, they found oxidative damage,
and those free hydroxyl ions that we were talking about
were causing damage
at a sort of invisible subcellular level.
After exposing the research Zoanthids
to 20, 40, 60,
or 110 micrograms per liter of copper,
and that's almost directly convertible
into parts per billion by the way,
the Zoanthids contracted
and they were noticeably less flexible and harder to cut
compared to the control polyps.
Their bases where they grab onto the rock
were also filled with algae
that normally wouldn't be present there.
The copper broke some kind of barrier or membrane
inside the polyp that would normally prevent that algae
from reaching the base of the polyp.
Looking at the Zoanthids under a microscope
they found that the walls of the polyp
were much thicker after exposure
to even 20 parts per billion copper
over about nine to 11 days.
The copper caused the Zoanthids to produce
much more collagen, and that thickened the walls
and also made them less flexible.
The thickening also reduced the internal space
that the coral could use for food and water flow
and all that kind of stuff that's important for its life.
Coral is not the only ocean animal that suffers
from collagen issues after exposure to copper.
Sponges have been found
to actually have the same thing happen.
After placing a sponge in some contaminated sediment
in the ocean and letting it grow over time,
its tissues thickened, leading to less water
being able to flow through the sponge.
And of course, since sponges rely on filtering water
and moving the water through its tissues,
that is bad news for the sponge.
In fact, the same thing can actually happen to you.
No, not water problems and things like that,
but chewing on Areca nuts, also called Betel nuts,
forgive my pronunciation, that leads to increased levels
of collagen in the tissues of your mouth.
In extreme cases it can get tough enough to prevent you
from even being able to open your mouth at all
'cause you can't stretch your lips anymore.
That's called oral submucous fibrosis,
and it can actually lead to mouth cancer.
There are a few different ways to test for copper,
and the way you test for copper actually depends
on the type of copper compound that you want to find.
An ICP test is gonna be the most accurate
at the very low end, and so if you're not dosing copper
as a medication or something like that, then an ICP test
is probably your best bet for detecting
very low levels of copper reliably.
If you're dosing Cuprion or Cupramine
then the test kits that you need to use
are either the Seachem or the Salifert test kits.
If you're using Coppersafe or Copper Power,
you need to use the API test kits instead,
'cause there's different copper compounds
in use throughout those products.
Copper is actually a really interesting element
in reef tanks.
It's necessary for life,
but at just a tiny bit higher concentration
it leads to all those free radicals and overproduction
of collagen that toughens the coral's tissue and blocks
the normal life processes that our coral
needs to be able to perform in order to survive.
Those effects are additive, and we don't really know
if they return back to normal after the copper is removed.
Some of the changes, like the damage to DNA,
could very well be permanent, another reason
to keep copper far away from your coral.
Even if a level of copper isn't outright lethal
and doesn't just immediately kill your coral,
there is still damage being caused.
Let me know what you think down below in the comments.
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