still dialing in Ca RX

[snowmansnow]

the issue I'm having in dialing in my Ca RX is that my ALK raises.


after 24 hours of running my alk went form 9.5 to 12

my setpoint is 6.60 with a hyst of .03

my bubble count is 1 / sec

I'm concerned that if I raise my set point any higher I won't be dissolving the media as I should.

advice?

thanks,

B

 

[grouper therapy]

What is the effluent drip rate?

 

[snowmansnow]

It's not quite a stream ... I'll go measure

 

[snowmansnow]

I'm right at 2 oz / min

58 ml...right?

 

[grouper therapy]

SnowManSnow;821883 wrote: It's not quite a stream ... I'll go measure

I'd slow that back and see what happens

 

[snowmansnow]

Ok..
I'll see what can do

 

[snowmansnow]

Ok I'm at 58ml / 2min 15 sec

Which is around .....
29ml / 1min 7 sec

How's this rate?

 

[grouper therapy]

Is that around a drip a second?

 

[snowmansnow]

No about 2..

I'll try to go 1 / sec

 

[grouper therapy]

Stay at 2 for a day or two and check results. IMO

 

[acroholic]

SnowManSnow;821871 wrote: the issue I'm having in dialing in my Ca RX is that my ALK raises.


after 24 hours of running my alk went form 9.5 to 12

my setpoint is 6.60 with a hyst of .03

my bubble count is 1 / sec

I'm concerned that if I raise my set point any higher I won't be dissolving the media as I should.

advice?

thanks,

B

I'd just raise the setpoint myself. Keep the effluent rate/bubble count constant and raise the reactor setpoint until you reach the KH level you want. Reactor media dissolves up to pH 7.7 in the reactor chamber.

Reference: http://www.reefkeeping.com/issues/2002-05/sh/feature/">http://www.reefkeeping.com/issues/2002-05/sh/feature/</a>

One thing to be aware of, however, is that other factors can affect your KH. Your salt mix can affect that as well. I thought I was having a huge amount of KH added when I had a Nilsen stirrer and my rector going at the same time. But turns out that my Instant Ocean salt mix was going into the tank with a KH of 12, and I do pretty large water changes. So this was artificially spiking my tank KH.

To me, it is just easier to adjust the reactor pH setpoint while maintaining a constant effluent rate and bubble count. Very adjustable as well, since the Reefkeeper can adjust the reactor pH to a hundredth of a unit of pH.

But what Dave suggested would work as well. I just prefer to push buttons on the controller. Keep your hysteresis low and you will also maintain a more steady KH. I keep mine at .01. A hysteresis of .00 was having the AP.com valve clicking on/off too much for me.

 

[grouper therapy]

Adjusting the effluent rate will also give the media more dwell to utilize the available co2 and will less likely to waste co2 into the system. 60 drips per minute or less is what is usually recommended to start with by most of the reactor manufacturers. Like Dave said either will work. One way = Higher flow/ lesser concentrated effluent ,the other =lower flow /higher concentrated effluent.

 

[schwaggs]

Assuming you are using a controller to manage the pH level in the reactor and you have a CO2 administration rate high enough, higher flow only means more of the same concentration effluent being added to the system. This is the main reason, IMO, to use a pH controller on a CA reactor. If your flow drops, for whatever reason, the pH controller effectively drops the CO2 administration rate preventing you from melting your media.

Right or wrong, I manage mine the same as Dave, I tweak the pH to meet my tanks needs.

 

[darren24]

One day when I grow up I will be as smart as you guys.....

 

[grouper therapy]

I believe either way is fine and works well. I will say that too high of flow through the reactor with a ph set to dissolve the media can most definitely limit it's output and dump unused CO2 into the system. I found it easier to maintain a constant drip rate rather than steady stream.

 

[acroholic]

A steady drip just shy of a stream should be in the 55-65 ml/minute range. Not many systems that rate won't work for.

 

[grouper therapy]

Acroholic;822099 wrote: A steady drip just shy of a stream should be in the 55-65 ml/minute range. Not many systems that rate won't work for.

For sure.

Edit: I always viewed mine as a dosing system for the alk. I set the reactor ph level at the highest set point possible but low enough to dissolve the media . I then viewed it as container filled with the calcium/alk combo and then dosed according to the systems need. Made it very simple for me.

 

[snowmansnow]

Still working on it

I'll eventually dial it in!