When I first got into reef keeping, the hobby appeared extremely daunting.

I felt I needed to be an engineer, biologist, chemist and several other "ists" all rolled into one in order to be successful.

There is so much information, so many "must-have" gadgets and so many chemicals that must be monitored and dosed it made my head swim.

One thing made clear to me from the start—something experienced reefers and shop owners I spoke to unanimously agreed upon—was the importance of maintaining proper calcium and alkalinity levels inside your reef aquarium.

ESV B-Ionic 2-Part Calcium Buffer

With my first couple of reef tanks, I used two-part solutions (specifically E.S.V. B-Ionic or Two Little Fishies C-Balance) to help me maintain calcium and alkalinity. As my coral collection and knowledge of the hobby grew, so did the size of my aquariums. Manually dosing my tank soon became an everyday thing. I knew there must be a better way!

After doing some research and speaking with other hobbyists, I decided it was time to try a calcium reactor. To this day, I still regard adding a calcium reactor to my reef aquarium as one of the best investments I've ever made in this hobby. It simplified my daily tank maintenance and helped automate my system to a certain extent.

Your reef aquarium may now be at a stage in its development where a calcium reactor would be enormously beneficial, making upkeep easier and corals flourish. But how do you know for sure when it's time to get a calcium reactor?

You're in luck, fellow aquarium lover. I've put together a list of the Top 4 signs you should be on the lookout for to let you know it's time for a calcium reactor.

AquaMaxx Star S-1 Calcium Reactor Package 2


When the amount you spend on two-part supplements is higher than your electric bill, it might be time to get a calcium reactor.

I'm exaggerating to make a point, but if you're adding gallons of two-part to your reef tank to maintain calcium and alkalinity levels each month, my example may no longer seem off base once you start doing the math.

If you have a small tank, like a nano reef, you may never find yourself in this position: a couple of bottles of two-part and a disciplined maintenance routine and you'll be straight for months. For larger reef aquariums, you may end up dumping quite a bit of two-part solution into your tank. As days, weeks, months and years pass, the time and cost of dosing can really add up!

While the initial monetary investment in a calcium reactor is pretty hefty (as far as aquarium equipment goes), the long-term costs are minimal comparatively speaking. Sign into your Marine Depot account to check how much you're spending annually on two-part supplements to determine if a calcium reactor may make more fiscal sense.

Reef Tank Parameters Chart


When you find that your tank is so demanding you actually forget to dose any one of the many additives you are using, it's probably a good time to start shopping for a calcium reactor.

Back in my two-part dosing days, I would occasionally forget to add vital chemicals to my tank due to work or play. This is a serious no-no! As we all know, keeping water parameters stable is extremely important to the health and vitality of reef tanks. Corals can show signs of improper care rather quickly; neglecting your dosing regimen for even a few days may cause issues.

Once you've dialed in the settings of a calcium reactor, there is very little left to do. A quick check each day to ensure the CO2 bubbles are bubbling properly and that effluent water is dripping at the appropriate rate is about all you'll need to remember.


If your water parameters are constantly fluctuating, I would suggest looking into a calcium a reactor.

I mentioned it earlier, but it bears repeating: stability is one of the major keys to having a healthy tank. Sure, dosing two-part solutions and kalkwasser are effective ways to maintain calcium levels. But they can also cause levels to rise quickly (when first dosed) and drop gradually over the next 24 hours while consumed by the livestock in your tank. The cycle continues each time you dose: levels quickly rise and then fall.

A calcium reactor provides a steady supply of calcium and other elements into your water to provide a more stable, ocean-like environment... which is really what we're all striving for anyway.

Innovative Marine SR-120 Shallow Reef Aquarium


If your corals are beginning to outgrow your aquarium and you're considering moving to a bigger tank, that's an ideal time to work a calcium reactor into your new & improved reef aquarium system.

There's no reason you can't set up and run a calcium reactor from the start of a new tank. As the calcium demands of your new tank increase from new coral frags and colonies, you can adjust the settings of your calcium reactor and dial them in to match the increased uptake by your livestock.

Korallin Calcium Reactor 1502 Package 2


Once you've got your calcium reactor settings dialed in, there really isn't an easier, more stable way to maintain calcium and alkalinity in your reef tank.

Like a lot of equipment in this hobby, calcium reactors may initially appear to be too complicated to set up for the average reefer, but this simply is not the case.

With a little time and patience (and help from your friends at MD), you can get a calcium reactor up and running in no time! I explained how to set up a calcium reactor in one of my earlier articles if you're curious about next steps.

If you think it may be time to upgrade to a calcium reactor, contact us today and we'll help you select the right equipment for your specific tank. We'd love to hear from you!