How quickly does your calcium reactor use up CO2?

Discussion in 'General Reef Discussion' started by capman, Feb 28, 2019.

  1. capman

    capman I contributed!
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    For the past month or so I've had my calcium reactor going on our big tank in the lab (something like 350 gallons total system volume). It seems like it is going through CO2 much too fast.

    If you run a calcium reactor on a similarly sized system (or on any system), how quickly do your CO2 cylinders get emptied?

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    Prior to running the calcium reactor, we were needing to add about a half liter each of each part of the BRS two-part supplements (calcium chloride and soda ash), each day, to keep up with uptake by the system.

    For about a month I've been running the calcium reactor (a reactor built by Bill Wann) with a target pH of 6.5 for inside the reactor (controlled by a pH controller and solenoid valve).

    We have a central CO2 system in our department, with two LARGE (like, at least 4 feet tall) CO2 cylinders and CO2 lines going out to various labs. In no more than a month, both of our large CO2 tanks have been emptied (they were full at the start). And the only thing using the CO2 this past month was my calcium reactor.

    This depletion of the CO2 seems far too fast. There were some suspicions of problems this past summer as well when the CO2 was being used in a tissue culture incubator in another lab. We are suspecting some sort of leak somewhere in our CO2 system.
     
  2. OP
    capman

    capman I contributed!
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    TIm, zoolan70 , how much CO2 do you go through (and in what time period) on your large tank?
     
  3. nubbs

    nubbs Senior Member
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    On my 215 total volume system my small tank (5lbs) lasted 10.5 months.

    I think you are right to suspect a leak somewhere.

    Sent from my SM-G955U using Tapatalk
     
  4. zoolan70

    zoolan70 I contributed!
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    You've got a leak. My 10# tank will last me 6+ months, and I run down at 6.2. What is your flow rate through the unit?
     
  5. OP
    capman

    capman I contributed!
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    I was running it at 40 ml per minute (with pH in the calcium reactor hovering around 6.5) - this is basically a fast drip - but it wasn't keeping up with demand by the system. So, I've gradually increased it up to 100 ml/min.

    Today I decided to drop the pH in the calcium reactor down to 6.3 - 6.4 or so, hoping that that might increase the ability of the reactor to meet the tank's demand.
     
  6. zoolan70

    zoolan70 I contributed!
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    I would drop the pH in the reactor to try and increase dissolution instead of increasing flow. The faster the water flows through, the more CO2 it takes with it and then out-gasses. If you find that the media is turning to mud, then raise your pH and your flow.
     
  7. OP
    capman

    capman I contributed!
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    Thanks.

    I dropped the pH to 6.4 the other day. This seems to have helped. Maybe I'll try 6.3.

    As for the CO2 usage problem.....
    Another person in our department examined the entire CO2 system in the department (we have something like five places where CO2 lines come in to various labs for various purposes), and he found one of the CO2 valves was leaking a little bit (was not turned off all the way) in one of the other labs. That was a waste of a lot of CO2.

    Our CO2 cylinders are scheduled to be exchanged next week. It looks like I'll have to go back to two part for part of the week, but then maybe all will be fine.
     
  8. jlanger

    jlanger "The North Remembers"
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    Whoops!
    Do any of the lines have pressure gauges that can be used to pinpoint leaks? If each line has a valve at the beginning of the run (with a pressure gauge down the line), you can close the valve (thus turning off the supply to the line) and see if the closed line loses any pressure over time.
    I only know this because I just had to perform this test with my new regulator.
     
  9. OP
    capman

    capman I contributed!
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    I'm not sure how this is all set up. But my impression is that there are valves and regulators at the cylinders, and then in the four or 5 locations in various labs where the CO2 is potentially used. I'm not sure whether we have the ability to do what you are suggesting. I really don't know.
     

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