- (relaxed background music) Did you know that
setting up a calcium reactor on your tank
may wind up to be the number one source
of phosphate pollution as soon as you turn it on?
Is it something that you can solve
or are calcium reactors destined to be
the last thing I'd ever recommend using again?
Find out today.
(upbeat chime)
Today we not only answer that main question
about calcium reactors and phosphates,
but along the way,
we'll also answer what calcium reactor media actually is.
How coral skeletons versus mined media
can greatly affect your reactors performance,
and what role choosing to run a calcium reactor
can play on your tank's pH.
A while back we conducted a series of investigative tests
on calcium reactor media to find out their concentrations
and how different flow rates and pH values
changed those concentrations.
Within that testing, I also sought to answer
if calcium reactor media added any trace elements
back into the tank.
Well, if you were hoping that it did, spoiler alert,
our ICP test results showed that very little, in fact,
hardly any trace elements were present.
However, what was extremely surprising to see
from those ICP test results
was just how much phosphates there were
instead of trace elements.
So that's where today's experiment picks right back up
in order to find out how much phosphate pollution
calcium reactor media adds to our tanks.
We plan to feed our reef octopus reactor with a large vat
of freshly mixed hw Reefer salt water,
then let it run for 24 hours
using the four most popular media options,
CaribSea, Triton, Two Little Fishies, and Korallen-Zucht,
and then test the effluents for any added phosphates.
Just by looking at all four of these media types
side by side, you can visually tell that each one
is some different form of calcium carbonate.
Actually there's three polymorphic forms
of calcium carbonate being Aragonite, Calcite, and Vaterite.
And two of those, Aragonite and Calcite,
are very popular in our hobby,
which you might've seen before in choices for sand, rock,
and in this case, calcium reactor media.
Although Aragonite and Calcite share the same chemical
formula as calcium carbonate or CaCO3,
the main difference between the two is in the configuration
of their atoms and crystalline structure.
The exact geology and process
of how Aragonite and Calcite are formed
can quickly get complicated.
However, it would be pretty safe to delineate the two
with this basic understanding
for the purposes of today's tests.
Aragonite is primarily formed
through biological and physical processes
like corals building skeleton
or inverts building protective shells,
which can either be as recent as the last decade
or as old as thousands of perhaps millions of years ago.
Calcite on the other hand,
can be the primary calcium carbonate form
in various limestone formations
or under different environmental conditions,
even marble or dolomite with a much denser structure.
First step for our testing was to find
a reactor pH setpoint for each media type that provided
as close to a 30 dKH effluent concentration as possible.
After that, we let each type run through a reactor
for 24 hours, then ran a series of tests
for phosphates in the effluent.
Starting with a baseline phosphate reading of 0.04
from the hw Reefer salt water, we tested the most popular
CaribSea ARM Aragonite media first,
and found that at 6.1 pH there was an average of 29.77 dKH.
As for phosphates, the ARM media tested
at an average of 0.12, which is 0.08 parts per million
more phosphate than the source water.
What that means is if you were to apply this to a standard
reef tank running at a common average of 30 mils per minute,
in a single day, you would turn over 43.2 liters
or about 11 and a half gallons of tank water
with three times higher phosphates than normal.
And when you add that extra phosphate pollution
to your daily feeding schedule,
you can quickly see how phosphates can become
even more of a time and effort challenge to steadily manage.
So up next is the Triton calcium reactor media,
which is the densest material of the four
and is actually the only Calcite marble based media
in today's test.
To reach an average of 30.07 dKH,
We pH'd the reactor to 5.9 and tested an average
of just 0.03 parts per million phosphate,
which is basically zero added phosphate,
given the plus or minus accuracy
of the HANNA Ultra Low Range Checker.
The next media is one that we've used for years
on the BRS160 and the 750XXL,
and also a super popular choice among the reefing community.
The Two Little Fishies ReBorn media.
We found an average of 27.47 dKH at just 6.5 pH,
making it the highest pH melting point we'll see today.
However, it averaged 0.83 phosphates,
or just under 21 times the amount of phosphates
than the hw source water.
the fourth was the KZ Aragonite reactor media
that tested at 30.9 dKH with a reactor pH of 6.1.
There were registered phosphates in the effluent
of 0.07 parts per million, or just 0.03 higher than the hw.
However, the crystalline of this media is much denser
than the other Aragonite medias.
So now we have three Aragonite based medias
registering phosphates and one Calcite based media
that measures zero.
But how could that be?
I believe that the answer lies in the differences
between their crystalline structure
and the process by which each were formed.
Let's explore that calcium carbonate formation piece first.
Thinking back to earlier in the video,
I said that it's relatively safe to consider Aragonite
to be formed from natural processes
like coral building skeleton or inverts building shells.
While you could assume that calcite is formed
through higher pressures and temperatures.
Now, any geologists would probably scoff
at this very rudimentary way of thinking about it,
but follow along with me here.
First, we have coral skeleton bits with
the highest phosphate pollution of the medias we tested.
Look at the structure of the material.
It is very porous and obviously looks like dead coral.
And because all living things
use phosphorous and nitrogen to live,
and because we are sourcing this material
in the closest form to the actual living creature
that developed it, the potential for it
to have higher phosphates bound inside seems logical.
Now looking at the CaribSea ARM
with the second highest phosphate pollution,
it's crystalline is definitely denser
than the coral skeleton bits,
although some pieces still resemble old corals.
I would be willing to bet that this material is
a more ancient or older calcium carbonate in coral skeleton
that was likely exposed to heavier pressures
or maybe even different temps over time,
which may have degraded the bound up phosphates
to some degree.
In stark contrast to that the KZ Aragonite media
crystalline structure is significantly more dense
than the other two Aragonite options,
and surprisingly enough had 40% less phosphate
than the CaribSea ARM.
I would either guess that this form of Aragonite
is either mined from ancient coral beds or possibly
a different geological form of Aragonite altogether.
So does that mean that any form of Aragonite media
will have added phosphates,
or that any form of Calcite media won't?
That's one question that will definitely need
more exploring and research to say definitively,
but given the data that we found today,
I think we can more confidently answer the question of
which media type you would you use
if you wanted to run a calcium reactor on your tank.
Here's what I would suggest.
If low tank pH is already a challenge for you,
but you've got your nutrient control dialed into a point
where you know exactly what levers to pull
when phosphate and nitrate levels change,
media like Two Little Fishies ReBorn is a great solution.
However, if pH is less of a concern
and you'd rather not have to plan
for additional phosphate pollution beyond your foods,
my choice would be the KZ Aragonite reactor media.
But what if you're somewhere in between
those two tank issues of pH versus phosphates?
Is there a way to get the lower phosphate benefits
of the KZ media,
but the higher pH melting point of the ReBorn?
Can you gas off the excess CO2 from the effluent
and raise the pH before it goes back into your tank?
Find out in this BRStv Investigates next.