Things you will need to install and tune in your reactor
• The complete reactor as provided by the manufacturer
• Arragonite Media
• Cobalt MJ feed pump (any size)
• CO2 system including the tank, regulator, needle valve, and solenoid and bubble counter*
• pH meter, calcium and alkalinity test kits (recommend Salifert)
*The electronic “carbon doser” type regulators do not require the use of a bubble counter
Set up and installation instructions
The manifold and fittings are shipped loose to help prevent damage in transit and to allow a
compact shipping container. These parts will need to be installed before any other steps are
taken.
1. With the lid removed from the reactor thread the pumps intake manifold into the fitting
found in the center of the lid. Take care not to over tighten this part, while it is a sturdy
unit keep in mind you are dealing with plastic. Thread the manifold until you can see no
more threads from the underside of the lid. Turn the manifold so it is oriented opposite of
the other holes in the lid and between two keyholes.
2. Install the feed barb (located in the bag with the probe gland) into the threaded hole in the
lid. The O-ring will create a watertight seal*, there is no need for pipe thread sealants on
this fitting. *If you have trouble finding the correct tool to install this fitting thread seal
tape can be used.
3. Install the probe gland into the hex shaped pocket on the lid. Make sure the O-ring is on
the dry side of the lid for proper seal. No pipe thread sealants are required for this fitting.
Tighten the nut on the underside of the lid hand tight plus a quarter turn.
You will now want to give the reactor a thorough rinse to remove any residual glue, dust or fabrication debris.. Before
installing the media you will also want to give it a rinse to help remove any dust. Fill the reactor with media up to about 2”
from the top of the chamber. After the media is in place install the lid and tighten the thumb screws in a staggered bolt
pattern like you would do while installing lug nuts on a wheel. Do not over tighten the thumb screws. With the lid secure
install the MJ1200 circulation pump by threading the union half on the manifold to the union half on the pump. The black
tube can now be attached to the pumps output and secured with the snap grip hose clamp. Pliers may be used on the clamp
but take care not to over tighten. You can turn the manifold in its threaded lid connection to obtain a smooth bend in the
rubber tubing. It is also perfectly fine to trim the tubing if needed. The idea is to have a nice smooth curve between the
pump and the chamber.
It is a good idea to give the reactor a bench test at this point to insure there are no leaks. This is best done at the kitchen
sink. It is much easier to remove and re-tape a leaking fitting now than after the reactor is installed and under your
aquarium cabinet.
Once confident the reactor is leak free, install the unit to its final location. Attach the reactors feed pump with the fitting
installed in the lid and place the return (effluent) line into the sump above the water level. Be sure the micro ball valve is
in the “open” position. Having the micro ball valve open while filling will allow the reactor to purge air.
Install the co2 system according to the manufactures instructions. If using a pH probe remove the plug in the probe gland
and install the probe in its place. It is now safe to feed water into the reactor by plugging in the feed pump. Do not plug
in the circulation pump until the reactor is filled with water. Once the reactor is filled and water is
being returned to your sump, plug in the reactor’s circulating pump. Allow the reactor to run like this for a period of time
as air is released from the media.
Once the reactor is in place and running you can start introducing co2 into the unit by opening the valve on top of the co2
tank. Adjust the pressure dial on the regulator to 10 pounds maximum, or to manufactures recommendations. Close the
CO2 needle valve and then plug in the solenoid. You are now ready to dial in the reactor.
NOTE: A wide open valve and introduce too much gas pressure causing damage to the
reactor!
Dialing in Your GEO Calcium Carbonate Reactor
Before attempting to dial in the reactor you must first understand how the reactor operates. Water in the
reaction chamber is being circulated through the media many times per hour. Water is fed through the
reactor rather slow, being just ml per minute. CO2 is slowly added to the reaction chamber and this allows
the pH of the water to drop to an acidic level. This in turn allows the media in the chamber to break down
and add elements to the water in the circulation loop. As water from your aquarium is fed into the loop,
water from the reactor rich in calcium and carbonate ions is allowed to drip back into the sump.
Two adjustments will affect the reactor effluent, CO2 bubbles per minute.(BPM) and the effluent drip rate.
Increasing the BPM will raise the effluent alkalinity and lower the effluent pH. Increasing the effluent drip
rate will raise the effluent pH and lower the effluent alkalinity.
Before dialing in the reactor you will want the target values for the aquarium in place. Manually adjust
these values with the appropriate buffers. You will also want to record the values of each test to track the
effect of your adjustments during dial in. There is no set rule for BPM to gallons of water as aquarium is
very different in demands and each reactor would be tuned in to meet those needs. I recommend a
starting point of 20ml per minute (NOT DROPS) and a slow BMP of 5-10. It is better to start slow and
ramp up the values than to start too high and attempt to dial down. Let the reactor run for twelve to twenty
four hours between each adjustment and test to see the results. After the initial adjustment you should
see an increase in the effluent alkalinity and a drop in pH. If the aquarium values have dropped, increase
the BMP. If the aquarium values have remained consistent or increased, allow the reactor to run as is and
retest after the given time period. I suggest an increase of BPM no more than a few at a time, remember
we to go slow. As you are testing and adjusting the BMP, you will also want to keep track of the effluent
pH, do not allow this to drop below 6.0 (depending on media used) for a long period of time. Below a pH
of 6.0 the media will quickly dissolve and turn to a mushy state. Once this has happened, the flow through
the reactor is hampered and performance will greatly suffer. If you do see the effluent pH below 6.0, make
adjustment to the effluent drip rate, increasing as needed. As a general rule, the effluent alkalinity will be
between 2 and 3 times that of your aquarium alkalinity.
An effluent pH of 6.5 is typical of most set ups and a good number to target but anything below 7 could
work.
It is important to find the balance of the co2 gas to the effluent rate. Once dialed in the solenoid should be
open almost all the time so the flow of gas into the reactor is stead and consistent. The controller (if used)
should not be used to regulate the pH but as a safety. A constant flow of gas into the reactor keeps the
pressure in the chamber stable and goes a long way in keep the effluent drip consistent.