Precision Marine is finishing out the year strong, adding a few more products to their already well-rounded lineup. Their newest release is the RFCa640 reverse flow calcium reactor. In the past, PM used Eheim pumps for their reactors, more specifically the 1048 and 1250 models. This new reactor, however, will feature a Sicce Syncra 3.5 recirculating pump. This model Sicce puts out over 630 gallons per hour, leading me to believe this PM calcium reactor is designed for the big boys. The RFCa6 reactor, for example, is rated for aquariums up to 400-gallons. Its pump, the Eheim 1250, only pushes 317 gph. Connecting the dots a little, I would assume the RFCa640 would be rated for tanks well over 500-gallons, potentially even more.

Pricing, availability and tank ratings haven’t been released for the RFCa640 yet, but they are already being added to PM’s website and the info will be available shortly. Plus, it would appear there is larger model of the RFCa series in the works as well. But again, details have yet to be seen at this point.

GEO 618 Calcium Reactor

In setting up my frag tank and future aquarium, I’ve accumulated quite a bit of equipment. I scoured ReefCentral for good deals, and for some reason I’ve been crazy for calcium reactors. Initially, I was going to have a 225-gallon aquarium so I found and purchased a GEO 624 calcium reactor. It is rated for approximately 400 – 450 gallons. Then I decided to downsize the tank slightly, to about 187-gallons, and fearing I would have constant pH issues with an over-sized calcium reactor, I decided to downgrade the reactor as well.

Deltec PF601 Calcium Reactor

I was able to find a brand new GEO 618 (rated for 350-gallons) for a steal. I got it, then had a few setbacks with the main aquarium…that being not having one and postponing it a little while. To quench my aquarium needs though, I started the frag tank, which is approximately 80-gallons. A week ago, I found a good deal on a Deltec calcium reactor, again on ReefCentral. I had always wanted a Deltec reactor, since they have a fluidized design which uses less CO2, and of course I purchase it. This Deltec is a PF601 is rated for over 500-gallons! Needless to say, I will not have issues keeping the calcium levels elevated. But now, this leaves me with a GEO 618 to put on an 80-gallon frag tank. I guess I’ll just have to stock both aquariums to the max with hard corals.

Calcium Reactor Setup

After receiving multiple requests from fellow hobbyists to walk them through setting up a calcium reactor, I’ve decided to make a step-by-step guide on setting one up for their reef aquarium.

To start, you must determine the size reactor you will need. The average calcium reactor is rated for aquariums about 200-250 gallons and moderately stocked. But more hard coral dominated aquariums may need larger reactors. Smaller reactors are available, but the larger reactors are typically used to allow more flexibility.

After the size reactor is determined, begin shopping for the equipment. The reactor itself should be from a recognized manufacturer/vendor, and should be rated for aquariums larger than what you currently have. This will allow you to stock your aquarium more heavily, but also allow you to upgrade to a larger aquarium in the future. When picking out a calcium reactor, look for models that include a bubble counter, a recirculating pump that flows from bottom to top (more effectively uses CO2), and is made of quality material such as acrylic. Also make sure that the top of the reactor is easily removable, making maintenance and replacing of the media an easy task.

Aragonite Calcium Reactor Media

Image Courtesy of Marine Depot

In addition to the calcium reactor, you will need to purchase several other pieces of equipment. A CO2 cylinder, CO2 regulator with a needle valve, pH controller, Calcium Carbonate (CaCO3) media, a small pump to feed aquarium water to the reactor, and CO2 resistant tubing are all required pieces needed to complete your calcium reactor setup. The CO2 tank is an aluminum cylinder that houses CO2 under pressure. The CO2 regulator attaches to the aluminum tank and performs two functions. It monitors the available CO2 in the cylinder and delivers CO2 to the calcium reactor via the precise needle valve. The pH controller monitors the pH of the effluent water (water leaving the calcium reactor), allowing you to raise and lower the pH of the effluent water to suite your aquarium’s needs.

Deluxe Dual Gague CO2 Regulator

Image Courtesy of Marine Depot

Once all of the equipment is purchased it’s time to assemble the calcium reactor setup. Begin by opening up the reactor, pouring in the desired amount of media, assembling the PVC fittings, and reattaching the lid. Next, attach the feed pump and let the calcium reactor fill with water. After the reactor fills with water from the aquarium, and is subsequently pouring effluent water back into the aquarium, start the recirculating pump. At this point in the assembly, check for leaks and fix them. Now it’s time to connect the CO2 equipment. Attach the CO2 regulator to the cylinder and slightly open the knob on the cylinder. Do not open the knob on the cylinder all the way. Just open it a 1/4 turn of the knob. Then as CO2 is flowing into the bubble counter on the calcium reactor, adjust the needle valve on the CO2 regulator and decrease the effluent flow rate. Most calcium reactor manufacturers have desired guidelines, but I like to start it out the pH a little higher, the bubble count a little lower, and the effluent flow a little slower. This will prevent alkalinity from climbing too high too fast and pH from dropping too far. But as a general guideline, set the effluent water flow to 40 drips per minute with 10 bubbles per minute of CO2. Then, adjust the pH (via the controller) to approximately 6.5 to 6.7.

pH Controller

Image Courtesy of Marine Depot

Once the reactor is running, it’s time to fine tune. Adjust the bubble rate, effluent flow, and pH of the setup in order to optimize your CO2 use and aquarium pH. Be sure to test your water for pH and alkalinity, as these two are the most crucial to the chemical balance at this stage. Let the calcium reactor run for about 24 hours, then retest your parameters. The alkalinity should have increased, but it should be under 12 dKH. If it is too high, decrease the CO2 input and increase the pH of the effluent water. Continue adjusting until you reach stable levels of pH and alkalinity, and your calcium isn’t decreasing or increasing. Also keep in mind that the calcium reactor is not designed to increase your calcium level in your aquarium, but maintain it. So don’t worry if your calcium levels aren’t increasing. To raise your calcium levels, I recommend dosing with a liquid calcium supplement until you reach the desired calcium levels.

CO2 Cylinder

Image Courtesy of Marine Depot

This is hopefully a fairly thorough calcium reactor setup guide. If you have any questions, feel free to email me at admin@aquanerd.com and I’ll respond as quickly as I can.

Warner Marine King Kong Calcium Reactor

*Picture Courtesy of Jon Warner and Reef2Reef

I’ve recently found some pictures of a huge calcium reactor made by Warner Marine. This thing is a beast, and is so rightfully named the King Kong Calcium Reactor. The King Kong dwarfs all others. It is reported to have five chambers, is 30″ tall, and has a main that is a whopping 8″ in diameter. Apparently this reactor is special order only, is estimated to fetch about $900, and can handle tanks in excess of 600 gallons.

Check below for more pictures of this beast.