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Re: [APD] copper

Alkalinity is the important parameter, not so much pH, although
in most systems, pH and KH are corrleated well.We add cO2, that
changes the pH, but does nothing to KH.

This needs to be considered anytime folks want carry on about
the importance of pH.

It's not the direct pH effect, it the secondary causes that
causes trouble for folks, lowering KH, negelected tanks etc.

Copper has a very long aquatic herbicide history.
Having recently written an articel for the BarrReport on Cu(due
this month) and Fe(last month), high copper levels do not
inhibit Fe uptake, although they do use the same uptake
transport system. The issues are not one of competition for the
uptake site, rather, one of good concentration over time,
activity/strenght of the chelators(both can and often do have
chelators) as well as some other issues (both are very low in
our tanks in terms of what is normally found is soil, which is
where such information is based on inhibition, unless you
discuss the concentrations required for inhibition, the comments
about copper/iron inhibition ___REALLY HAVE NO MEANING_.) If you
accept such arguements, then you could say adding excess Iron
could also inhibit copper uptake.
Without knowing the ranges, you really have little useful

> I was wondering whether excess copper in the water column will
> cause
> problems with rotalla species/sagiteria/ludwigia. What are
> copper poisoning
> symptoms?

Copper complexes(chelates) act as plant cell toxicants and may
inhibit photosystem II electron transport. Herbicide activity is
greater when plants are photosynthesizing and may be reduced on
submersed aquatic plants if there is not adequate penetration of
light into the water or if plants are covered with silt or
algae. Copper is taken up by aquatic macrophytes and
translocated, although the element is not metabolized, and it
may be stored or excreted. Copper complexes are not sub ject to
photolysis or volatilization.

In general, plants are fine with less than 0.4ppm(this rate,
.2-.4ppm is very effective killing algae, but folks here and
everywhere else seem to think they rather pay 100X as much for
snake oil), some plants can handle 10X this amount though.
Plant control is general at .6-1.0ppm ranges.

In general, Cutrine will not harm plants but will kill
algae(it's weaker formulation), likewise, Komeen will kill algae
and plants(the stronger formulation).

Unlike snake oils and harsher chemicals, you can measure copper
and monitor it.

I'm not sure why so many folks whine about copper killing their
shrimps etc, from their trace element mix, it's virtually
impossible, although like Dave's case, your pipes might have
more to do with it.

At least one person needed RO/heavy metal removing filters as
they had 2ppm levels out of the tap. Buy a test kit, calibrate
the test kit, then see.

I've done a lot of copper monitoring and AA and spect work for
weed control professionally.
> My rotallas have no new growth when placed in the suspect
> water. They do not
> grow, and simply turn black and then rot away. The ludwigias
> have trouble
> rooting now (as did the stellata) as the root area just turns
> black and dies
> up towards the leaves.

So did you also place non suspect control water as well?
Otherwise it might be some totally unrelated.

 In addition, my shrimp have been dying
> off after
> water changes, and i see yellowing on some of the sagiteria
> leaves/other
> plant parts. The yellowing is not due to nitrates/iron/sulfate
> since i know
> exactly how much is in the tank, and it is far above
> deficiency levels.

Sometimes they do change things like the KH/GH, I've seen shrimp
die for strange reasons even when I use RO and the same ferts. 

Plants sound like you need more traces. 
> There is a sign in one of the buildings next to my tank that
> warns people
> "This water has high copper levels, but the levels are not
> toxic to humans."

Sounds like you need to use some filters to remove it.

> I mean it all makes sense, my shrimp are dying, some of the
> sensitive plants
> are dying, sagitteria, ludwigia, wachilli and others still are
> showing
> symptoms.

Well, we all know that could be a dozen different things.
Do many folks test for copper that make claims about it?

Haha, seldom if ever.
"What's a test kit?"
Copper levels drop fairly fast in planted tanks.
A high initial levels will drop, Fe is similar there.

You don't test once a week, you test each 30-60 minutes or less.

> I did a bit of research on Cu symptoms, and one thing that
> high copper does
> is limit the uptake of
> so
> symptoms show up.

I think you need not worry about that, I think you are seeing
direct attack of PSII inhibition, this is far more serious than
a Fe blocking ever would be(that would be much more subtle, if
you can see it at all in aquatic plants).

Basically you need so much you'll kill the plant before you
block the uptake.

> What do you think i should do? 

RO, heavy metal filter.
For you more than the fish and plants.

Also what are the levels of
> copper that are
> toxic to plants?

Now there is the right question. 

 I bought a test kit thats accurate to 0.01
> mg/L that should
> be comming soon. Hopefully that will be sensitive enough to
> tell what is
> going on. 

Generally they tend to be decent oddly. .2ppm or high is cause
for concern, if you have low KH's, you need to worry more.
Copper is more toxic at lower KH's, say 4 or less.  

In addition, i will be testing the water at the lab
> for copper, so
> i will probably be able to obtain a much more accurate
> reading.

Then use the AA rather than spects.
Copper should impact plants within 24-48 hours or less.
Same for algae if not sooner.

You can then remove it with water changes, heavy metal filters,
DI resins etc.

There is a large variance within plant to plant species
impacts(as well as KH variation tank to tank etc), if you use it
as an algicide, start low and slowly ramp it up progressively
noting impact on plants. You should not need to go over .4ppm
for effective algae control.

Had-a-snail is 1.61% copper from copper sulfate pentahydrate.
TMG is 0.006% , flourish is 0.00005% copper sulfate, plantex is
0.10% CU. Had-a-snail takes multiple uses to kill pond snails,
and you darn near have to squirt it directly on the snail at
that, so I can't imagine the trace amount in ferts having any

Seems like you have a high copper issue really though coming in
from the tap.

Consider the options I suggested.

Tom Barr


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