Can Only Get Effluent in Calcium Reactor to 14.4 dKh

[PeterC99]

Installed new Reef Octopus CR140 Calcium Reactor last month. Have only been able to get effluent to about 14.5 dKh. Have read that it should be about 25 dKh.

CO2 comes on from solenoid at 6.4 and goes off at 6.8. Have Octo VarioS Controller pump at level 3. And Kamoer peristaltic pump set at 30/ml per minute.

Any recommendations to get dKh higher?

Thanks!

 

[Biff0rz]

How big is the unit, how much media does it hold, and what media are you using? Also I'd recalibrate the PH meter in the unit to verify its value. I'd then hold a tighter gap between high and low of the PH, more towards the lower end.

 

[Pwnm30rdi3]

Is the reactor keeping up with the tank demand at 14.5dkh?

I’m running ~15dkh effluent at 25ml/min and it is keeping up with my current tank demand. I don’t feel the need to chase a lower PH or higher dkh effluent output at the moment.

 

[PeterC99]

The calcium reactor is rated up to 200 gallons. My aquarium is 90 gallons.

Using CaribSea 1 Gallon ARM Reactor Media - Extra Coarse. Using whole container which fills the reactor up over 3/4 of the way.

 

[PeterC99]

Is the reactor keeping up with the tank demand at 14.5dkh?

I’m running ~15dkh effluent at 25ml/min and it is keeping up with my current tank demand. I don’t feel the need to chase a lower PH or higher dkh effluent output at the moment.

Reactor is not really keeping with Alk demand with 14.5 dKh. Neptune Trident tests Alk every 6 hours. Alk has dropped from 8.75 to 7.65.

 

[Biff0rz]

The calcium reactor is rated up to 200 gallons. My aquarium is 90 gallons.

Using CaribSea 1 Gallon ARM Reactor Media - Extra Coarse. Using whole container which files the reactor up over 3/4 of the way.

Reactor is not really keeping with Alk demand with 14.5 dKh. Neptune Trident tests Alk every 6 hours. Alk has dropped from 8.75 to 7.65.

So if you tested the effluent properly, you need to lower the PH in the unit, this is why I say recalibrate the PH probe, it may be off.

How did you test effluent alk? I take 2.5ml output plus 7.5ml rodi and use a Hanna tester than multiply x4 to get the output value, but again, the PH needs to be accurate. If the PH is correct then you're putting in the correct amount of CO2 which makes the correct effluent output.

Once the output is correct then you can dial in the effluent output flow to match the tanks needs.

 

[Biff0rz]

Btw 14.5 seems pretty low alk for a CaRx. Mines at like 60 lol. Melting media like woah.

 

[Biff0rz]

Sorry for the spam but once you have the output alk figured out you'll want to test every 48hrs and use this calculator (on the right) to dial it in.

Calcium Reactor Setup Help

 

[PeterC99]

So if you tested the effluent properly, you need to lower the PH in the unit, this is why I say recalibrate the PH probe, it may be off.

How did you test effluent alk? I take 2.5ml output plus 7.5ml rodi and use a Hanna tester than multiply x4 to get the output value, but again, the PH needs to be accurate. If the PH is correct then you're putting in the correct amount of CO2 which makes the correct effluent output.

Once the output is correct then you can dial in the effluent output flow to match the tanks needs.

Re calibrated pH probe twice and believe it’s accurate. Does this Carib Sea Ciurse media need a very low pH to melt?

tested effluent directly from reactor

 

[Biff0rz]

Re calibrated pH probe twice and believe it’s accurate. Does this Carib Sea Ciurse media need a very low pH to melt?

Most media melts below 6.7 (I think). I use 2lf media, no exp with Carib Sea but they should be similar.

How did you calibrate the ph meter? Did you use low range or high range reference fluid?

Also this is how tight I keep my ph in my carx chamber

If pH-CAL > 6.67 Then ON
If pH-CAL < 6.64 Then OFF

 

[PeterC99]

Most media melts below 6.7 (I think). I use 2lf media, no exp with Carib Sea but they should be similar.

How did you calibrate the ph meter? Did you use low range or high range reference fluid?

Also this is how tight I keep my ph in my carx chamber

If pH-CAL > 6.67 Then ON
If pH-CAL < 6.64 Then OFF

For Neptune Apex pH probe, you have to calibrate with Both low and high calibration solution.

 

[FMF0331]

I also use TLF reborn media, i tried ARM..did nothing for me, switched back to Reborn
Now it's just impossible to get

My effluent is reading 15, but it's meeting the demand of my frag tank

 

[Biff0rz]

For Neptune Apex pH probe, you have to calibrate with Both low and high calibration solution.

There are 3 solutions. 4,7,10. Did you calibrate with 7/10 or 4/7?

PINPOINT pH High Precision Calibration Fluid

Pinpoint pH calibration fluid is carefully prepared for maximum precision and accuracy. Each packet of PINPOINT pH Calibration Fluid contains ample fluid for calibration (about 30mL). Keeping your probes calibrated will lead to more reliable readings allowing you to know exactly what is going on...

www.bulkreefsupply.com

I used 4/7 to calibrate my carx PH probe.

 

[Suohhen]

It certainly smells of testing error to me. The probe that comes with the Apex, if that is what you used, is unreliable especially if not freshly calibrated. Mine varies by. 3ph at calibration and then quickly falls further out of calibration.. Imo a double junction lab grade probe is the way to go for a calcium reactor.

 

[Biff0rz]

It certainly smells of testing error to me. The probe that comes with the Apex, if that is what you used, is unreliable especially if not freshly calibrated. Mine varies by. 3ph at calibration and then quickly falls further out of calibration.. Imo a double junction lab grade probe is the way to go for a calcium reactor.

Boom. Yea, I'm not using an apex junk probe. I have two probes - one for the tank and one for the carx. The tank one is just a cute reference one, the carx one is for accuracy.

 

[Suohhen]

The other common cause of low alk is a blockage of flow through the media. Since it has only been up for a month it is unlikely that the media is clogged although if it wasn't fully rinsed it could be possible. It is also possible that the pump has slowed or stopped but again 1 month? unlikely.

 

[stephj03]

Coarse and extra coarse ARM have required lower ph to melt well for some.

You could:

1. lower the rpm on the feed pump to lower ph without changing your CO2 flow.

2. Set your controller to shutoff CO2 at a lower ph

3. Reconfigure to a CO2 always on approach.


I would prob reccomend 1/2 for now but 3 in the long run.

 

[Rick.45cal]

So for ARM media 6.8 is too high a pH and won’t dissolve much, 6.4 is probably about right to start getting good dissolution of the media. So your pH swings in the reactor are too large, you need to keep the reactor closer to 6.4 and it will produce far more alkalinity and Ca. For a calcium reactor to be most efficient it needs to attain an internal equilibrium of CO2 injected, the volume of incoming tank water (flow rate) and the pH of the incoming water, then you will get consistent stable dKh levels in the effluent. So keeping the variables you control (CO2 and flow rate) constant is important to attain equilibrium within the system.

Which brings me to my next point that most “control” oriented aquarist overlook. Having your controller open and close the CO2 solenoid is actually counter productive to this. It’s far more efficient (and actually easier on you) if you keep the CO2 solenoid open and limit the injected CO2 to exactly what you need. This accomplishes several things. An equilibrium within the reactor is easily achieved and maintained (unless you make a change to the CO2 amount or flowrate), pH inside the reactor becomes nearly constant (small daily swing based on the pH swing in the tank from day to night). The reactor can never “run away” from you, (because the only variable that produces Alk or Calcium is CO2) and there’s no pH probe that can and will ”drift” between calibrations. The result is a highly stable alkalinity in the effluent and your tank dKH becomes stable.

I’ve operated my CaRx both ways, and the “old school” manual way is far easier and more efficient. The last 3 years of running my system this way I have only had to make a major adjustment when I change my bottle which is a 20# tank and it last almost a year. (I dissolve about 23-30 lbs of media in that time).

 

[PeterC99]

There are 3 solutions. 4,7,10. Did you calibrate with 7/10 or 4/7?

PINPOINT pH High Precision Calibration Fluid

Pinpoint pH calibration fluid is carefully prepared for maximum precision and accuracy. Each packet of PINPOINT pH Calibration Fluid contains ample fluid for calibration (about 30mL). Keeping your probes calibrated will lead to more reliable readings allowing you to know exactly what is going on...

www.bulkreefsupply.com

I used 4/7 to calibrate my carx PH probe.

Neptune has 2 pH solutions 7 and 10 ph. No other options.

 

[PeterC99]

I also use TLF reborn media, i tried ARM..did nothing for me, switched back to Reborn
Now it's just impossible to get

My effluent is reading 15, but it's meeting the demand of my frag tank

Any suggestions where to get Reborn media?

Also See Reborn on certain supply sites but looks like ARM stuff.