How do CaRx flow rates affect effluent potency? | BRStv Investigates

Users Who Are Viewing This Thread (Total: 1, Members: 0, Guests: 1)

How do you adjust or tune your calcium reactor?

  • Peg pH and adjust flow rate.

    Votes: 8 34.8%
  • Peg flow rate and adjust pH.

    Votes: 6 26.1%
  • Adjust both pH and flow rate.

    Votes: 7 30.4%
  • Other approach? (Share below!)

    Votes: 2 8.7%

  • Total voters
    23

randyBRS

BRStv Host :-)
View Badges
Joined
Dec 9, 2014
Messages
2,124
Reaction score
3,969
Location
Minneapolis, MN
Rating - 0%
0   0   0
Part two is here!

In the last BRStv Investigates episode on calcium reactors, we determined that there are some change in dKH potency (or max saturation points) at each pH set point and the differences were pretty sizable.

This week, we find out if increasing the flow rate to 4x, 8x, 12x, 16x, even 20x faster than the original 5mL/min.... has any effect to those max potency levels!


 

Joe Grubbs

Active Member
View Badges
Joined
Oct 1, 2015
Messages
105
Reaction score
36
Rating - 0%
0   0   0
Before taking down my CA Rx (mid-2018), I maintained a constant low flow with a lab grade pump, and adjusted the CarbonDoser bubble rate based on the Alk of the aquarium. I did monitor pH in the CaRx and it ranged in the area 6.4-6.6 but, I did not control on this value.

The CaRx recirc pump failed for the 3rd time in 6 years (about a 24 month life span) and I took this opportunity to move to Kalk dosing. The result is that Tank pH has increased from running 7.8-7.9 to now runs in the 8.0-8.1 area...note: this is also the time I focused on ICP testing and trace element adjustments...I see a clear and corresponding change in coral growth due to this set of changes.

I'm strongly considering re-starting the CaRx and looking forward to info from this series before doing so.
 

ispookie666

Active Member
View Badges
Joined
Sep 8, 2017
Messages
132
Reaction score
64
Location
Suffolk, UK
Rating - 0%
0   0   0
Thank you for the fantastic experiment.

Does altering the max saturation matter when you are holding the pH constant? I'm a bid dubious of the hypothesis. Looks like it's a show down between the reciculating pump and Kamoer, looks like kamoer won!

I personally fee the graph is flawed.
You need to have the Y axis as Total dKH and x axis as flow rate. Using just the dKH/ml does not convey a clear picture.
 
OP
OP
randyBRS

randyBRS

BRStv Host :-)
View Badges
Joined
Dec 9, 2014
Messages
2,124
Reaction score
3,969
Location
Minneapolis, MN
Rating - 0%
0   0   0
Before taking down my CA Rx (mid-2018), I maintained a constant low flow with a lab grade pump, and adjusted the CarbonDoser bubble rate based on the Alk of the aquarium. I did monitor pH in the CaRx and it ranged in the area 6.4-6.6 but, I did not control on this value.
The CaRx recirc pump failed for the 3rd time in 6 years (about a 24 month life span) and I took this opportunity to move to Kalk dosing. The result is that Tank pH has increased from running 7.8-7.9 to now runs in the 8.0-8.1 area...note: this is also the time I focused on ICP testing and trace element adjustments...I see a clear and corresponding change in coral growth due to this set of changes.
I'm strongly considering re-starting the CaRx and looking forward to info from this series before doing so.

In upcoming tests for CaRx's, I plan to test the effectiveness of various ways to increase pH before the effluent gets to the tank or other ways to mitigate low pH in the tank. :)
 
OP
OP
randyBRS

randyBRS

BRStv Host :-)
View Badges
Joined
Dec 9, 2014
Messages
2,124
Reaction score
3,969
Location
Minneapolis, MN
Rating - 0%
0   0   0
Thank you for the fantastic experiment.
Does altering the max saturation matter when you are holding the pH constant? I'm a bid dubious of the hypothesis. Looks like it's a show down between the reciculating pump and Kamoer, looks like kamoer won!
I personally fee the graph is flawed.
You need to have the Y axis as Total dKH and x axis as flow rate. Using just the dKH/ml does not convey a clear picture.

I think the common understanding is that the max saturation (with the pH pegged) will decrease as you add more flow through the reactor, due to a perceived less contact time with CO2 inside the reactor. In the first CaRx test we sought to find out what those max saturations were at each pH setpoint (6.2-7.2) and then armed with that info we sought to challenge that the max saturation would decrease with more flow (~"less contact time").

In this case, the graph shows the Y-axis as total dKH of the effluent output from our baseline, and then what that total effluent dKH was after running the reactor for 24hrs @ 20mL/min; then 24hrs @ 40mLs/min; 24hrs @ 60mLs/min... and so on. We can see that from the max saturation baseline for both 6.4 (23.1dKH) and 6.8 (40dKH) that increasing the flow by 4x-20x there is a change to the max saturation, but pretty nominal at best.
 

ispookie666

Active Member
View Badges
Joined
Sep 8, 2017
Messages
132
Reaction score
64
Location
Suffolk, UK
Rating - 0%
0   0   0
Using mEq/L might make my point a bit clearer. The total alkalinity would be flow rate x mEq/L so for the higher flow rate your total alkalinity output would be higher even if your alkalinity drops.
 
Last edited:

bubblemytip

Active Member
View Badges
Joined
Jan 4, 2017
Messages
374
Reaction score
438
Location
New Zealand
Rating - 0%
0   0   0
I use an aquacare turbo. I peg flow and pH and then just adjust the time the reactor runs. The reactor runs based on co2 saturation with a float switch. Its internal pH is about 5. Flow rate is 70ml/min. Only runs 10 hours a day at the moment.

The media is a spherical pharmaceutical grade calcite.

The reactor has a chamber to increase the effluent pH back to 7-7.3, using a counter-current airstone set-up, then it has a de-sedimentation chamber at the top, before it hits the tank, so the display pH never drops below 8.

93A7329F-679B-4399-B403-47C5725345C1.jpeg


Works pretty well on my 90-gallon sps tank:

1035F966-1A19-4E81-8B52-94DCB79F0C05.jpeg
 

ispookie666

Active Member
View Badges
Joined
Sep 8, 2017
Messages
132
Reaction score
64
Location
Suffolk, UK
Rating - 0%
0   0   0
upload_2019-3-30_17-53-4.png

I have done a bit of jiggling around with your data and converted it to meE/L and using the flow rate used to calculate the output per hour.
X axis is flow rate per minute
Y axis is Alkalinity ouput in mEq/L/Hr

If you are looking to increase the output of the reactor - this graph probably puts things into perspective
 

Welcoming coral to your home!!! How do you add coral to your tank?

  • Move the coral from the bag and place it directly into the display tank.

    Votes: 11 8.9%
  • Dip process before placing the coral into the display tank.

    Votes: 82 66.1%
  • Acclimate before placing the coral into the display tank.

    Votes: 16 12.9%
  • Move the coral from the bag and place it directly into the quarantine tank.

    Votes: 0 0.0%
  • Dip process before placing the coral into the quarantine tank.

    Votes: 8 6.5%
  • Acclimate before placing the coral into the quarantine tank.

    Votes: 3 2.4%
  • Other.

    Votes: 4 3.2%
Back
Top