Calcium Reactor questions.

REEFRIED! · Nov 5, 2023

Hello, I am going to put a calcium reactor on my 120. First off I am one of those people who went with a color scheme in my plumbing, sump, and equipment. However the calcium reactor will not fit under my tank, and will be in a separate cabinet so I am not locked into color scheme! I know most people don’t care but I am a bit anal. I vacuum my sump weekly.

Anyways, I am looking around at calcium reactors. Geo’s (which may be the gold standard for hobbyist grade CR’s). Reef Octo, and lastly Aquamaxx. I have read reviews, watched videos and done a good amount of research. Essentially what it comes down to is basic. A calcium reactor is a tube that holds media, mixes in CO2, dissolves the media and returns high alkalinity effluent back to the tank. So I am not sure I can justify spending $800 on a reactor, when the Aquamaxx is $275 and has had solid performance over the few years they have been out. With that said, I am not cheap. I have no problem spending the money. I spent about $7500 before I put water in my tank. All of my equipment is top notch. I just can’t figure out why there is a $500 price difference.

Which brings me to one of my questions. The older reef octo calcium reactors have an AC pump non speed adjustable. The newer ones have the varios DC controllable models. I use a varios return pump and love it. I also use a reef octo skimmer and I love it also. Both of those have good use for a controllable DC pump, both in power draw and in controllability. Makes sense to be able to dial in a return pump and skimmer pump. I just can’t for the life of me figure out why you would need to change or adjust the flow of a CR recirculating pump? For years people ran AC pumps and only had one speed option. Even the newest Geo’s CR’s come with a reliable DC pump but it is not speed controllable. I can get the older model Reef Octo for half of what the varios line costs. Is there any reason why I should not go with that? I am not worried about power draw or really concerned about noise.

Also if you have any input regarding the three brands I mentioned please let me know.

Thank you

Jason_MrFrags · Nov 6, 2023

I am partial to RO since that I've ran the last 10yr. Cheaper and works great, easy to get replacement parts. I did upgrade the pump to the varios, but more b/c I use the same pump for skimmer and UV/heat loop. So now only need 1 spare backup pump on hand. I do believe RO is having a decent sale coming up.

jda · Nov 6, 2023

No reason to have a DC pump on a reactor. None. My guess is that this is offered for folks who want to feel cool having digital over analog?

I have used a ton of reactors. Reverse flow, ehiem pump are key, IMO. The Ehiem pumps can run dry if your reactor fills up with co2.

If you want to use a pH probe, then you need a port. I DO NOT EVER recommend using a pH probe to control co2, but you can use it to monitor.

A little tube that extends down at the top to trap excess co2 can really help you tune. This is not a dealbreaker since you can install one, but reactors like Korallin have them already. The reactors also need to be reverse flow in most cases. This feature allows co2 to get trapped inside of the reactor and can tell you if you have a bad tune.

I have a few Korallin and also a newer AquaMaxx that I won at a local club raffle. The AquaMaxx are fine. They are reverse flow and I have added a bit of pipe from the inlet to allow co2 to get trapped. The AquaMaxx that I have has a filter floss pre filter that keep junk out - love it since it keeps gunk out and hate it since I have to clean it a lot.

REEFRIED! · Nov 7, 2023

jda said:
No reason to have a DC pump on a reactor. None. My guess is that this is offered for folks who want to feel cool having digital over analog?

I have used a ton of reactors. Reverse flow, ehiem pump are key, IMO. The Ehiem pumps can run dry if your reactor fills up with co2.

If you want to use a pH probe, then you need a port. I DO NOT EVER recommend using a pH probe to control co2, but you can use it to monitor.

A little tube that extends down at the top to trap excess co2 can really help you tune. This is not a dealbreaker since you can install one, but reactors like Korallin have them already. The reactors also need to be reverse flow in most cases. This feature allows co2 to get trapped inside of the reactor and can tell you if you have a bad tune.

I have a few Korallin and also a newer AquaMaxx that I won at a local club raffle. The AquaMaxx are fine. They are reverse flow and I have added a bit of pipe from the inlet to allow co2 to get trapped. The AquaMaxx that I have has a filter floss pre filter that keep junk out - love it since it keeps gunk out and hate it since I have to clean it a lot.

Thank you for the reply. That’s what I thought. No reason to have a controllable pump on a CR. Obviously having a DC pump is better for power draw, however it’s not a deal breaker. I may just go with the older Octo model. Maybe I will upgrade eventually to a varios pump. I can probably do that for less than the newer models cost.

I have read your CR guide to tuning and I am leaning towards not using a ph controller to run it. Even if I decide to do it that way I will use your model to learn how to tune it without first.

YOYOYOReefer · Nov 7, 2023

I would recommend older used calcium reactors all day. I’ve got old korralin and mrc reactors, you are right the designs not changed they are simple devices. I would say go with the reactor that’s got the thickest acrylic I woul put much more thought into regulator choice than worry about which brand of acrylic reaction chamber.

control. I’ve always used ph controllers but I just unpacked a kamoer Kh carer from the coralvue outlet store on sale for $510. I’m hooking it to a small old koralin reactor now to experiment with. the alkalinity controller should be able to control the reactor. I will use my ph controller as a fail safe on the effluent. in case the kamoer gets off track. Going to test on a little tank and see if this might be truly cruise controlled alkalinity pump

YOYOYOReefer · Nov 7, 2023

I would say get an ac pump like a pan world or iwaki to run the reactor Those last for decades and have been proven to work ,and are designed to work with head pressures are made for all sorts of real chemicals.

Js.Aqua.Project · Nov 7, 2023

What is your favorite ice cream? I am a mint chocolate chip guy, but you might be a fan of chocolate or vanilla, or maybe even strawberry or pistachio. I just know I need a bowl big enough to fill me up when I want some.

When it comes to calcium reactors the only true thing that matters is the size, is it big enough to hold enough media to be able to supplement your tank. The AC/DC pump choice doesn't really matter.

For my 240 I am using a GeosReef CR612X2 because that's what I got a good deal on and it was big enough to get the job done.