What did you do to your tank today??

Sep 22#18

@janiners305 wrote: We've got the pH probe inside the CaRx also. We are running our old Geo 618 I think it is. On our old 135g, this reactor was the best thing we did. It helped the most with growth and color. Hubby is looking at the Kamoer FX-STP2 I think right now...we are just running the needle valve at the moment.

GEO makes really nice, high-quality products. If possible, I would add a second chamber to degas the low pH coming out of the reactor. I have a CR618 +SMC618 on the 150gal. Yes, I absolutely love calcium reactors - they’re super low maintenance, once dialed in! 😁 Check out this thread re: peristaltic pumps. I have no affiliation with this vendor/product. I’ve just ordered it as well since it’s $70 cheaper than my previous order. westcoastreefers.com/thread/cmthf6udn0002l4nt2a…

— /yolo

SCRM😎 Cool Kids🌸Polyp Whisperer

Joined Aug 202672 posts284 pts📍 Glendora, CA

Sep 22#19

@BackbayReef wrote: GEO makes really nice, high-quality products. If possible, I would add a second chamber to degas the low pH coming out of the reactor. I have a CR618 +SMC618 on the 150gal. Yes, I absolutely love calcium reactors - they’re super low maintenance, once dialed in! 😁 Check out this thread re: peristaltic pumps. I have no affiliation with this vendor/product. I’ve just ordered it as well since it’s $70 cheaper than my previous order. westcoastreefers.com/thread/cmthf6udn0002l4nt2a…

We do have the 2nd chamber! When we purchased our reactor back in the day, the reefer we bought it from included the 2nd chamber. The whole system was hardly used. I will definitely check out that thread. Thanks for that!

— 105 gallon mixed reef - SPS/Torch/Goni

SCRM😎 Cool Kids⚡SPS Slinger

Joined Aug 202688 posts364 pts📍 Porter Ranch, CA

Sep 22#20

@janiners305 wrote: We've got the pH probe inside the CaRx also. We are running our old Geo 618 I think it is. On our old 135g, this reactor was the best thing we did. It helped the most with growth and color. Hubby is looking at the Kamoer FX-STP2 I think right now...we are just running the needle valve at the moment.

I set up my CaRx to my tanks demands and I try to keep it as simple as possible. I use a masterflex as my feed pump (which pulls water through) at a constant rate, usually 50-60mL/minute. I then set a bubble count to reduce pH in the chamber just below the melting point of the media I'm using. I test alk about every 12hrs in the tank, if it's not where I want it to be, I simply add more co2, very small turn of the solenoid. Wait another 12hrs and test. Once I get to my desired dkh, I test occasionally to make sure all is well. This is how I've always used a CaRx running 24/7. I've modified this method now in order to keep pH from falling too much at night, so I only run the CaRx during daylight/photo period and kalk at night. If I need more alk, then I either add more kalk or simply add another hour of time "on" with the CaRx or simply adjust the co2. What media are you going to use?

— Clams and acros

SCRM😎 Cool Kids🌸Polyp Whisperer

Joined Aug 202672 posts284 pts📍 Glendora, CA

Sep 22#21

We are using the re-born media from two little fishies. It’s the same stuff we used before in the old tank.

— 105 gallon mixed reef - SPS/Torch/Goni

SCRM😎 Cool Kids⚡SPS Slinger

Joined Aug 202688 posts364 pts📍 Porter Ranch, CA

Sep 22#22

@janiners305 wrote: We are using the re-born media from two little fishies. It’s the same stuff we used before in the old tank.

Cool, it has a melting point around 7.5, so you don’t need a lot of co2 to get the job done. Two things to remember/consider with reborn. It adds PO4 to the system because phosphate is bound to the skeleton and it gets messy over time. I’m a heavy feeder, so I don’t need the extra PO4, which is why I use the Tunze calcium carbonate media, it’s super clean and it’s just pure calcium and alkalinity. Btw, I have the same reactor.

— Clams and acros

@BackbayReef

SCRM😎 Cool Kids🧠Reef Guru

Joined May 2026265 posts1,033 pts★5.0(2)

Sep 22· edited Tue, Sep 22 · 12:59 PM#23

@Drexl wrote: Cool, it has a melting point around 7.5, so you don’t need a lot of co2 to get the job done. Two things to remember/consider with reborn. It adds PO4 to the system because phosphate is bound to the skeleton and it gets messy over time. I’m a heavy feeder, so I don’t need the extra PO4, which is why I use the Tunze calcium carbonate media, it’s super clean and it’s just pure calcium and alkalinity. Btw, I have the same reactor.

Guess 3 of us have the same GEO CaRx then! I’ve been using 2LF for years but will look into the Tunze’s CC when I exhaust mine, which is likely a year from now! lol

— /yolo

SCRM😎 Cool Kids🌸Polyp Whisperer

Joined Aug 202672 posts284 pts📍 Glendora, CA

Sep 22#24

@Drexl wrote: Cool, it has a melting point around 7.5, so you don’t need a lot of co2 to get the job done. Two things to remember/consider with reborn. It adds PO4 to the system because phosphate is bound to the skeleton and it gets messy over time. I’m a heavy feeder, so I don’t need the extra PO4, which is why I use the Tunze calcium carbonate media, it’s super clean and it’s just pure calcium and alkalinity. Btw, I have the same reactor.

Thanks for the melting point. We will keep that in mind. As for the PO4, that’s not an issue either. Ours is usually undetectable on test kits, so we are dosing to keep it just barely detectable. Last test was 0.04, and nitrates were 2.5. I’m a heavy feeder too, but I think all of the corals are consuming most of the PO4.

— 105 gallon mixed reef - SPS/Torch/Goni

SCRM😎 Cool Kids⚡SPS Slinger

Joined Aug 202688 posts364 pts📍 Porter Ranch, CA

Sep 22#25

@janiners305 wrote: Thanks for the melting point. We will keep that in mind. As for the PO4, that’s not an issue either. Ours is usually undetectable on test kits, so we are dosing to keep it just barely detectable. Last test was 0.04, and nitrates were 2.5. I’m a heavy feeder too, but I think all of the corals are consuming most of the PO4.

Here’s my recipe/ratio for nutrient balance. It’s a molar ratio, so the key/goal is to be as close to 50 as possible. It’s not about the actual numbers, but there’s relationship with each other. Nitrate divided by phosphate, then multiply by 1.53 For example: N 3ppm, P 0.09ppm 3 / 0.09 x 1.53 =51 You’ll notice several things, algae growth on the glass will take longer, less weird algae overall, and most of all, good healthy growth of corals. PO4 is very important, so keep it in the “healthy “ range and you’ll be okay. My healthy range is > 0.05 - 0.2, with the sweet spot being closer to 0.1 give or take a little.

— Clams and acros

SCRM😎 Cool Kids⚡SPS Slinger

Joined Aug 202688 posts364 pts📍 Porter Ranch, CA

Sep 22#26

Rip clean before and after.

— Clams and acros

SCRM😎 Cool Kids⚡SPS Slinger

Joined Aug 202688 posts364 pts📍 Porter Ranch, CA

Sep 22#27

Part 2

— Clams and acros

SCRM😎 Cool Kids🌸Polyp Whisperer

Joined Aug 202672 posts284 pts📍 Glendora, CA

Sep 23#28

@Drexl wrote: Here’s my recipe/ratio for nutrient balance. It’s a molar ratio, so the key/goal is to be as close to 50 as possible. It’s not about the actual numbers, but there’s relationship with each other. Nitrate divided by phosphate, then multiply by 1.53 For example: N 3ppm, P 0.09ppm 3 / 0.09 x 1.53 =51 You’ll notice several things, algae growth on the glass will take longer, less weird algae overall, and most of all, good healthy growth of corals. PO4 is very important, so keep it in the “healthy “ range and you’ll be okay. My healthy range is > 0.05 - 0.2, with the sweet spot being closer to 0.1 give or take a little.

So with my last numbers of 2.5 nitrate and 0.04 PO4, I’m at 95.625. Yikes.🫣 I’m gonna retest today to make sure of where we’re at.

— 105 gallon mixed reef - SPS/Torch/Goni

SCRM😎 Cool Kids⚡SPS Slinger

Joined Aug 202688 posts364 pts📍 Porter Ranch, CA

Sep 23#29

@janiners305 wrote: So with my last numbers of 2.5 nitrate and 0.04 PO4, I’m at 95.625. Yikes.🫣 I’m gonna retest today to make sure of where we’re at.

0.04 is the testing error of most phosphate kits, so I always treat PO4 that low as zero. Also, it's nothing to worry about or something that you want to change rapidly, just slowly increase your PO4 levels and see what happens. Once you get to the 0.08ppm range, most corals do better overall. If you need or want to raise PO4, Randy Holmes Farley recommends using trisodium phosphate (food grade) as a DIY solution. 1.88grams into 1L of RO, 1mL of that solution will raise PO4 by 0.01 in 26g/100L

— Clams and acros

@BackbayReef

SCRM😎 Cool Kids🧠Reef Guru

Joined May 2026265 posts1,033 pts★5.0(2)

Sep 23#30

My ratio is way off but I don’t think too much about it. I’ve noticed that my corals do well if PO4 is between 0.10 and 0.20 and NO3 under 10. This tends to jump around depending on my feeding mood, esp with 40+ fish in the system.

— /yolo

SCRM😎 Cool Kids🌸Polyp Whisperer

Joined Aug 202672 posts284 pts📍 Glendora, CA