Dialing my GEO reactor

[jdieck]

<a href=showthread.php?s=&postid=9364400#post9364400 target=_blank>Originally posted</a> by racermike27
I am kinda curious as to what may have caused the pH to fall like that.

Changes in temperature throughout the day can change the setting of the CO2 needle valve, also remember that as the PH of the tank cycles with the day / night cycle also does the PH in the reactor as the input water PH is changing. When you initially observed that during the day the Alkalinity drops a little bit it is not that the corals are using more but as the PH increase with the lights so the PH in the reactor and thus the alkalinity addition drops a little bit.
This fluctuations are normal so when you get your final settings the key will be that despite this possible variations in average you get your consumption replenished throughout the day.
Finally you were right in the setting of the controller, it is always better to use it as a back up and not to control the CO2, the variability of the controller also adds one more variable as it will not really cut off and on with a lot of precision.

 

[racermike27]

Hey JD,

I am kinda glad you chimed in here!! I have been following your past posts online regarding reactor setup all along.

So I guess I should wait until the tank ALK comes back down.
When it comes back down what should my next move be in terms of getting it dialed in again? Do I start from scratch?
The setting was running pretty well for the most part until the mishap yesterday....
I found that running and getting the reactor to stay stable at 6.78pH with a drip rate of 75ml/min I was getting decent results although it may be too soon to tell.

So what I am guessing now is that once the ALK drops again I will start the reactor this time setting my controoler to have the solenoid close at 6.78 and hopefully have it hold around this value. Would this be right?

Any help would be great.

Thanks,

mike

 

[jdieck]

Once your Alkalinity drops to 10 dKh try again but now try about 60 ml/min effluent and maintain the effluent PH at 6.8 and wait three days between testings, If you get a testing out of wack try testing again, Our kits are not that precise and is not rare to find variances of +/- 1 dKh. Try taking the measurements at the same time of day.

 

[racermike27]

Thanks for the info...I will try that and post the results.
My next question is if I lower the drip rate won't I in turn increase the amount of ALK coming out because theoretically the pH would decrease because of more dwell time. Ah, but the controller would shut of the supply once the 6.78 is reached correct....

I think I just answered my own question..... anyhow after the 3 days and then testing I am supposed to get consistent reults continuously if tested everyday at teh same time right....
Say if I get the ALK back down to ~10DKH I would just want it to remain there all the time correct granted there will be fluctuations at night.

In the long run while running a reactor will the excess CO2 affect the tank? I have my effluent dripping near the outlet and inlet of my skimmer, so I am not sure how effective this is in driving off the excess CO2.

Thanks,

Mike

 

[jdieck]

That is why I mentioned maintaining effluent Ph at 6.8 That means also adjusting the CO2 bubble rate to the down side.
I would recommend reseting the reactor to shut the CO2 off at 6.5 and make the adjustments trying to operate without it.
You stated it yourself, Less wear and tear, less fluctuation and longer equipment life.
At 6.8 I do not think you will have too much excess CO2. the long term effect is the same as short term you already saw of dropping your tank PH between 0.1 and 0.2 units.
Once you get familiar with the setting you can play a bit with it.
As an example, you can increase the reactor's alkalinity ouput and only operate it during the lights on period. Dripping at the skimmer inlet gives me about a 0.05 to 0.07 PH units improvement in the tank PH but I am using outside air to feed the skimmer.

 

[asnatlas]

<a href=showthread.php?s=&postid=9364675#post9364675 target=_blank>Originally posted</a> by jdieck
Try taking the measurements at the same time of day.

Is there a particular time that is best ??

EX : Once lights have been on or off for a few hrs ?? Or does it matter ??

 

[racermike27]

I don't really think it matters as long as you measure at the same time of day to ensure results that are not skewed deu to pH imbalances throughout the day.

So if you are measuring at 6pm try to do it everyday or every 3 days at 6pm.... If you measure say at 12pm you may ge a slightly different or skewed result and may never really know if the reactor needs tweaking. In 6 hours alot can happen...

 

[jdieck]

Yes, it does not really matters.

 

[gasman059]

wait three days between testings, If you get a testing out of wack try testing again

Again b patient I agree with the above reamrks. Anyways I'm at 6.6 and have seen somewhat of an increase in my alk to 10.5-11.5 w/o any major critter changes.
THX jdieck for d input!

 

[asnatlas]

<a href=showthread.php?s=&postid=9364960#post9364960 target=_blank>Originally posted</a> by jdieck
As an example, you can increase the reactor's alkalinity ouput and only operate it during the lights on period.

Do you do this, only run your CA reactor duing your lighting period ?? I have never heard of this but would make since as the corals would only use media effluent while the lights are on or is aleast significanlty higher during this time, correct ??

Do you just have the water flowing through your reactor with the C02 turned off during the "night" time ??

 

[racermike27]

The reactor once set up correctly and dialed in should run all the time from what I understand.

 

[racermike27]

I only have mine off right now because I am in the process of dialing it in and I got a spike in my ALK so I am waiting for it to come down before I start the CO2 feed again. Right now it is basically just circulating.

 

[jdieck]

Corals deposit carbonate 24/7
What happens in the tank is that when the lights are ON photosynthesis consume dissolved CO2 from the water column thus increasing the PH. By operating the reactor during lights ON part of the excess CO2 added by the reactor will be consummed.
At night when the lights are off, respiration increases the amount of dissolved CO2 so with the CO2 of the reactor turned off you will prevent a compounded effect thus reducing the PH swing.
Alkalinity will vary some troughout the day but has no effect in the well being of the animals. A timer cutting off the CO2 (or power to teh controller) at night is all that is needed, you will leave the effluent running 24/7

My system consumes too much Calcium and Alkalinity to be able to shut off the reactor at night, 5 pounds of media per month (140 ml/min effluent and 200 bpm of CO2). Despite this PH variation is very small because I supplement with a Kalk reactor at night (3 gallons per day) and use reverse lighting cycle for the frag tank and refugium.

 

[jdieck]

<a href=showthread.php?s=&postid=9365132#post9365132 target=_blank>Originally posted</a> by asnatlas
Do you do this, only run your CA reactor duing your lighting period ?? I have never heard of this but would make since as the corals would only use media effluent while the lights are on or is aleast significanlty higher during this time, correct ??

Do you just have the water flowing through your reactor with the C02 turned off during the "night" time ??

Yes you only cut off the CO2 and let the effluent running so you do not need to change any adjustments.
Note that the reactor shall have twice the required capacity as it shall have twice the ouput in hlaf the time.

 

[racermike27]

I run my fuge on a reverse schedule as well.
With my controller set I don't think I will have this problem, right. I mean once the controller sees the correct pH it will just shutoff the gas.
My tank pH does not fluctuate really bad, the lowest it will go is 7.95 at night and in the day it is around 8.07 on a high day it will as high as 8.1

 

[racermike27]

jdieck,

do you feel that a tank should be run with both a Ca and Kalk reactor? Is there more stability running ti this way?

 

[jdieck]

<a href=showthread.php?s=&postid=9365446#post9365446 target=_blank>Originally posted</a> by racermike27
jdieck,

do you feel that a tank should be run with both a Ca and Kalk reactor? Is there more stability running ti this way?

Not necessarily, time will tell and is different for each system.