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5 Best Calcium Reactors For Reef Tank In 2023

Most tank owners will not know what a calcium reactor is. The word reactor could invoke a sense of confusion or even panic.

Usually, the word reactor is often associated with nuclear reactors.

However, calcium reactors are in no way linked to nuclear power and are perfectly safe for your tank space.

These devices are usually put in marine tanks and are used to re-circulate and move water.

Calcium reactors also rebalance the water. In particular, it reintroduces dissolved calcium into an aquarium.

Really, this product is especially important if you want to upkeep the water quality of your tank. Reef tanks in particular will benefit from a calcium reactor.

There are many things that a reactor will do for your tank. I will get into the specifics of calcium reactors here.

I will also show you the best calcium reactors you can get as well!

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Reef Octopus CR140

[amazon box=”B071CHVJCB”]

Octopus is known to make great marine aquarium supplies. And with this calcium reactor, they show just how high quality their products are. There are many features to love about this reactor.

From the fast pumps that help bring CO2 into the chamber, to the sturdy design and materials of the reactor itself.

Octopus is also highly versatile. You can put this reactor in with your smaller fifty gallons set up and up to a two-hundred-gallon marine set up.

This is great for customers that have a range of aquariums in their home and don’t want to buy a ton of different sized reactors.

Octopus comes with all the standard reactor parts, from a pump to sponges, to media chambers.

You will have everything you need with the calcium reactor. But do know that you will be paying a premium for the octopus product.

Quality like this is expensive, but it is a good investment. And, you even get a warranty included for your calcium reactor!


  • The pump in this reactor is of great quality and very fast
  • The Octopus reactor is great for very big marine tanks, up to two-hundred gallons of water
  • Has a great warranty for your reactor device
  • Very high quality and long-lasting marine product in general


  • Very pricy calcium reactor product that might not be in your budget
  • You have to put this together yourself, which might be hard for some tank owners

Check Price and Reviews on Amazon

Video: “Reef Octopus Calcium Reactor “

Reef Octopus CR220

[amazon box=”B073RMSTY3″]

The next calcium reactor product is even pricier. And, it also comes from Reef Octopus-like the previous reactor.

This reactor is definitely high end when it comes to calcium reactors devices.

It has even more capabilities and really helps maintain Ph and other elements found in marine water.

Even more so than other products I have mentioned before. There is a Ph gauge with this particular device, and it also keeps track of CO2 levels.

Very large marine aquariums will benefit from the Octopus calcium reactor. But not everyone will be able to afford this particular reactor as it comes in near the thousand-dollar price range.


  • Great powerful pump like other Octopus products
  • Can handle larger tanks up to five hundred gallons
  • Comes with a Ph measurer
  • Works on all aspects of water quality
  • Can measure your CO2 levels


  • Even more expensive than the Octopus CR140
  • Again, you will have to assemble this yourself

Check Price and Reviews on Amazon

AquaMaxx cTech

[amazon box=”B07MD3M1KL”]

The third calcium reactor I will talk about on this list is the AquaMaxx. It is more moderately priced.

So this could be a good product for tank owners who want to invest in quality reactors without overspending.

It’s under five-hundred dollars, but still over the two-hundred-dollar mark. It has plenty to offer you as well.

It’s a pretty large device and it really creates powerful water flow and calcium dissolving in marine tanks. In short, it mixes up your water just the way it needs to be.

In addition, the design of this device is impeccable. It is extremely sturdy and well made even when compared to the Octopus reactors.

And it is much easier to get this machine operating and put in your tank which is a plus!

On the whole, I really recommend going with this product. Small tanks won’t fit with the AquaMaxx, but if you have a big marine tank get this product.

It works with tanks up to five-hundred gallons, and it mixes your water fabulously.


  • The price for this reactor is not bad at all
  • The power of this device is great
  • Very durable calcium reactor
  • Amazing at gauging CO2 levels and Ph
  • Good reactor for big tanks


  • Not a great calcium reactor for a smaller setup
  • Price could still be too high for some

Check Price and Reviews on Amazon

Video: “Aquamaxx T1 Calcium Reactor | First Look & Why Im Using It”

Viaaqua AC10

[amazon box=”B000UZLQLM”]

Viaaqua is the perfect calcium reactor for small marine setups. This calcium reactor option won’t fit with every aquarium of course. But I still recommend this product.

Especially with less large tanks. You can easily put this on the side of your tank, and it is easy to use this reactor.

You won’t have carbon dioxide included in this particular choice. Still, with the price of this reactor, you aren’t missing out on much.

Overall, this Viaaqua model is a pretty basic, but highly functional calcium reactor!


  • If you have a smaller marine tank this is a good reactor
  • You can make some adjustments to the pump
  • Already pre-assembled
  • Not hard to use this calcium reactor


  • You won’t have a source of CO2 with this device
  • Won’t be the ideal choice of a reactor for bigger tanks though

Check Price and Reviews on Amazon

Viaaqua AC30

[amazon box=”B002440GL8″]

The Viaaqua AC30 offers more options for tank owners than the AC10 model. This is still a relatively small device.

But this particular reactor can be used in both small and larger marine tanks with ease.

You can use this on aquariums anywhere from fifty gallons to two-hundred. Viaaqua is not a luxury brand but it provides your tank with great features.

You can adjust the setting of this device. You also won’t have issues with clogging or poor water flow.


  • The price for this reactor is very affordable
  • Works with bigger tanks and small tanks
  • Does not clog easily
  • Viaaqua offers great value


  • The device is a little lengthy for some small tanks
  • Massive tanks might need a more powerful reactor

Check Price and Reviews on Amazon

Why You Need A Good Calcium Reactor For Your Marine Tank?

Video: “How it works : Calcium reactors explained the easy way | Reef FAQs”

In reef aquariums and other marine tanks, you need a certain level of calcium, as well as, carbonate in the waters.

These elements are ingested by your pets and keep them healthy and happy in their man-made environment.

For certain pets, having these elements is especially important. Corals, clams, algae, and a few other critters will use these materials for their bodies. This will help them to grow their skeleton, even when they are not in the ocean.

Many tank owners do not realize the importance of this step. But the water in a marine aquarium needs to be replenished properly with the right materials. This is where calcium reactors come in.

Reactors not only put calcium in the water, but they also adjust Ph to the right levels. CO2 is a big part of this process.

As it is mixed in the pump of this device with the water. It slowly dissolves the calcium and it also helps to lower Ph levels.

All of this helps create water movement and better tank conditions for marine pets. Really, calcium reactors are essential and re-circulate your water. This way your marine tank is ideal for your tank inhabitants.

You have to buy calcium media and put it in the chamber of your reactor for the device to work right.

But really it is not hard to operate these machines. The cost can be a lot though. But you have to buy and invest in a good calcium reactor.

How To Find The Best Calcium Reactor Product?

There are a ton of reactor features to consider when you are choosing your calcium reactor device. We’ll try to narrow down which features are best in this final section.

There is a lot to know of course. So this portion of the post will help you hone in on the essential information you need. For starters, make sure you are getting a reactor that is made from quality materials.

Make sure your reactor and the chamber are the correct shapes. It has to be shaped like a cylinder and they need to be designed well. These two parts are very crucial to the functioning of your reactor.

In addition, ensure that the water pressure is good for your calcium reactor and that it can indeed be adjusted. Not all tanks need the same level of power. So it’s better to have some adjustment capabilities.

Ph meters and CO2 meters are good to have in your reactor as well. They help you know that your calcium reactor is doing its job recirculating the water right. And doing this with the correct measurements.

Finally, always get a calcium reactor that suits your specific marine tank. You don’t want a reactor that is too powerful or large for your tank. And you don’t want a calcium reactor that is underpowered either.

So look into the specifications of the product you choose. The calcium reactors in this guide can work with a number of tanks. So choose the right one!

As a side note, get a reactor from a good brand as well. Some marine companies just don’t know how to make these devices. You want something that is reputable and well made.

And dedicated brands that have a good reputation will give you the results you want, even if they do cost a bit more.

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Calcium reactors are a necessary item for certain marine aquariums. They are especially important if you have a reef tank of any size. I talked about calcium reactors here in great detail of course.

You need to know everything you can about these products before you make a final choice. This is because there are a lot of brands and reactors that are not up to standard.

I brought up several great calcium reactors that perform well and are of the best quality. This way you don’t have to deal with subpar reactor devices.

In addition, the five reactors I talked about were some of the best calcium reactors you can currently purchase.

So look through these items well and make a choice. Hopefully, I have provided you with a calcium reactor option that is right for your marine tank!

Aaron Boyd
Aaron Boyd

Hello, I’m Aaron Boyd, the proud owner and author behind Aqua Movement. I hope my article was able to answer your questions. If you want to learn more about me, click the home icon above.

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