CO2 setup with PH controller

rajkm

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I purchased American Pinpoint PH Controller couple of weeks backs and finally set it up last night.


My KH is around 2.5 - 3 and I think I can maintain it there.


I have set the PH Controller as follows


Low 6.4


High 6.6


giving center value of 6.5


So that would maintain 22.6 to 33.2 ppm of CO2.


Is that the right numbers to aim for?


I put the PH probe in one of the compartments in the overflow sump of my all in one tank at back right next to the compartments with all my filter, so should give me a clean data without rouge stray current.


The PH controller is set on a timer to start 1 hour before Photoperiod.


Observation:


The solenoid kicked 1 hour before photo period, and by the time lights went on I was already at 6.4 ppm


it slowly ticked down to 6.6 when the solenoid kicked back in.


I did not change my CO2 bps and before today I used to have it on all the time at that level, which would mean I was injecting a lot more CO2, the reason some of my fish were also hiding all the time.


Anyways, can someone confirm my setup is correct


I.E


PH Controller connected to Timer.


Solenoid connected to PH Controller


6.4 thru 6.6 low and high targets for PH at 3 dKH.
 

Pikez

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The ph/KH/CO2 tables on the interweb are as accurate as astrology.

 


So your estimation of 22.6 to 33.2 is as accurate as my reading today, which say
s: "This is a good day to celebrate yourself." Indeed. :D

 


​Aim for a pH drop of 1.0 from your degassed tap water. For now, it's OK if you're 0.5 pH drop. Increase CO2 slowly over a period of days or weeks until you get to 1.0 drop when the solenoid turns off. At that point, you will have - no one knows how many ppm CO2. It doesn't matter. Watch your fish and your plants.

 


If you are new to pH controller, do the following:


1. Check your pH twice a day


2. Check your KH once a week for the first few months. Then once a month.


3. Calibrate your probe with pH 7 buffer once a month. Use DI water to rinse probe and pat dry when moving probe around. Don't let probe go dry. If you don't do this, you will get low accuracy but high precision. Not good.


4. Change probes once a year.

 


Be paranoid. Never trust pH controllers.
 

Greggz

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Yes, your set up is correct. As far as the set points, only you can decide, and it's not an exact science.


Keep in mind you do need to calibrate the probe. I have the same controller and I calibrate mine every week. It's usually off up to about .1 or so. So in my case, my 7.0 solution could read at 7.1. I just do it as part of my regular weekly water change routine.
 

rajkm

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Thanks for the replies.


I will aim for a drop of 1 PH.


I had checked the PH before controller kicked in using test kit and verified it against the controller when it started and both were reading around 7.3-7.4 So I am close to 0.8 - 0.9 PH drop.


I have put the tank water out to degas and will verify it to cross check again. I can't use tap water for reference since I usually do RO or mix it 50/50.


I did calibrate the probe before I put it on use.


I have ordered new buffer solution sets since I forgot to put it away and my wife threw it. I will re-calibrate the probe frequently.


I also ordered the KCL solution for storage when not in use.


The drop checker turned little lighter than lime green very close or equal to indicator solution. Usually by noon my drop checker is yellow.


As far as drop checkers go, I don't know if its a good or not. Generally if its equal to indicator solution its supposed to be good CO2 ppm so it might be ok but mostly I have always seen people trying to reach yellow.
 

tefsom85

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Pikez said:
"This is a good day to celebrate yourself." Indeed. :D

This is exactly my reading. I'm glad you caught me before I started celebrating! :cool:


In all seriousness, I think the key part here is to watch your plants and fish, as mentioned. The fish are easy to tell if there is too much CO2. Don't ask me how I know. The plants take more intuition, which I"m still working on but I can tell when things aren't right. I have a CO2 probe myself but I honestly only use it to tell me that I'm below the 'respiration desperation' threshold.
 

Pikez

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rajkm said:
The drop checker turned little lighter than lime green very close or equal to indicator solution. Usually by noon my drop checker is yellow.


As far as drop checkers go, I don't know if its a good or not. Generally if its equal to indicator solution its supposed to be good CO2 ppm so it might be ok but mostly I have always seen people trying to reach yellow.

Drop checkers are more accurate than astrology. Use it to get a general feel of things, but not to make tactical decisions. I was cleaning up yesterday - I found and finally threw out my drop checkers and solutions from a few years ago. Nuff said.
 

rajkm

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Tested the water sitting out and was reading ~7.2 so it means I am in the 0.6 - 0.8 range

Pikez said:
I was cleaning up yesterday - I found and finally threw out my drop checkers and solutions from a few years ago.

Going to do that myself someday, once I get more comfortable with the PH probe and the feeling part. :)
 

PhilipS

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rajkm said:
The PH controller is set on a timer to start 1 hour before Photoperiod.

The pH controller is on a timer? How do you figure it needs a timer? To do what?


What's the point of paying for the controller, then?


What is the natural pH of the tank?


My pH controller is on 24/7 and I am happy with the dissolved CO2.

Pikez said:
Drop checkers are more accurate than astrology.

Star Gazers know that Stars move faster than Drop Checkers.
 
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rajkm

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webskipper said:
The pH controller is on a timer? How do you figure it needs a timer? To do what?


What's the point of paying for the controller, then?


What is the natural pH of the tank?.

The PH controller is on timer because there is no advantage of injecting CO2 at night, or so I have been told.


I could leave it on 24/7, if that's the general consensus.


As I said in the earlier post, the tank water left out seems to read ~7.2. I have Eco-Complete substrate with very little wood. So there is nothing to keep the PH low. It's a Innovative Marine AIO so the water gets degassed overnight due to the sump in the back.
 

PhilipS

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Sump? Then no worries.


Mine is on 24/7 and I don't lose fish because of CO2. It's when I overfill the rimless tank.


If your fish and aquarium inhabitants are ok with 6.5 then just keep it as your low point. The pH controller can only regulate the pH per the probe. Lab probes are more accurate. More accurate means CO2 running more often. More often means someone is getting gassed.


Slowly bring down the pH over a few days.
 

rajkm

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Yes, the AIO's are great that way, however you lose a good 2.8" of realestate for scaping. It used to be a reef setup and didn't matter then and was a godsend for a apartment dweller, but since I went planted I am kind of hating it, but does a good job at the filtration.


I might go rimless. Saw a Aquatop 21 tall (http://aquatop.com/high-clarity-glass-aquarium-hca-24.html) today at my LFS. Have to figure out filter options in my cramped apartment before I jump in and buy it. Hate to go HOB but might be my only option if I go this route.