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Can CO2 micro bubbles cause incorrect drop checker readings?

Hi @dw1305
What I am looking for is how much in ppm CO2 is going to have degassed water at atmospheric 2500 ppm CO2.

Hi all,


<"[CO2] = P/KH = 3.87 x 10-4 atm/29.41 atm M-1 = 1.32 x 10-5 M"> which gives you <"3.74 ppm CO2"> when you substitute "3.87 x 10-4" with "2.5 x 10-3".

cheers Darrel
Thank you @dw1305 very much for solving it. I was looking for this for some time and finally can see the light. So what is the result in terms of CO2 ppm at a given pH drop. We know from scientific papers and your calculations that atmospheric CO2 levels of ~400 ppm make water equilibrium of ~0.5 ppm. We also know that residential areas may have atmospheric CO2 as high as 2 500 ppm and thanks to you we now know what equilibrium this makes and that is 3.74 ppm. By having this data we can calculate tank CO2 ppm range of a typical pH drop,

1.6 pH, 19 - 150 ppm CO2
1.5 pH, 15 - 120 ppm CO2
1.4 pH, 12 - 95 ppm CO2
1.3 pH, 10 - 75 ppm CO2
1.2 pH, 8 - 60 ppm CO2
1.1 pH, 6 - 48 ppm CO2
1.0 pH, 5 - 38 ppm CO2

I don't know but these ranges, or inaccuracies, are posible and are dependent on the level of house ventilation function. Also this can explain why some people have success with 1.0 pH drop and others don't unless they go for larger drop.
 
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Hi all,
We also know that residential areas may have atmospheric CO2 as high as 2 500 ppm and thanks to you we now know what equilibrium this makes and that is 3.74 ppm. By having this data we can calculate tank CO2 ppm range of a typical pH drop,
I'm guessing that 600 ppm CO2 is a more realistic CO2 level for houses etc. There are <"figures for the pH of Oceans"> under various atmospheric CO2 level scenarios. It is a lot easier for sea water, because it is pretty consistent world wide and fully saturated with dKH.

cheers Darrel
 
I got a room CO2 monitor today. Only a cheap one so I don't know how accurate it is, but I think it will tell me the difference between a bit and lots, and whether it's increasing or stable. It also measures temperature and humidity, and those readings match those on another monitor I already have, so it may be reasonably OK.
It read 556ppm to start with. Then I sat in the room, breathing; went to 880ppm after 3 hours, flashing a yellow alert!
1205ppm after another hour and a half, orange alert!
I opened the window; dropped to 786ppm in an hour. Alert status; green. :)
All very interesting, and needing further thought. :)

EDIT; Two more hours with the window open and it's down to 527ppm.
 
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I got a room CO2 monitor today. Only a cheap one so I don't know how accurate it is, but I think it will tell me the difference between a bit and lots, and whether it's increasing or stable. It also measures temperature and humidity, and those readings match those on another monitor I already have, so it may be reasonably OK.
It read 556ppm to start with. Then I sat in the room, breathing; went to 880ppm after 3 hours, flashing a yellow alert!
1205ppm after another hour and a half, orange alert!
I opened the window; dropped to 786ppm in an hour. Alert status; green. :)
All very interesting, and needing further thought. :)

EDIT; Two more hours with the window open and it's down to 527ppm.
Hi @sparkyweasel
This is bombshell news in details thanks for sharing. What kind of CO2 monitor you got if I may ask.
 
CO2 table
 

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What kind of CO2 monitor you got if I may ask.
It's this one;
Meter
Lots of sellers have what looks to be the same one, some are a bit cheaper but slower to arrive.
In fact mine was £12.55 but they have now put it up to £12.99, - I must be an influencer. :)
 
It's this one;
Meter
Lots of sellers have what looks to be the same one, some are a bit cheaper but slower to arrive.
In fact mine was £12.55 but they have now put it up to £12.99, - I must be an influencer. :)
Funny, I didn't know they are so inexpensive, I must be living under a rock. So, what about a homework, can you find under water one in this price range?
 
got a room CO2 monitor today. Only a cheap one so I don't know how accurate it is,
It's this one;
Meter
Lots of sellers have what looks to be the same one, some are a bit cheaper but slower to arrive.
In fact mine was £12.55 but they have now put it up to £12.99, - I must be an influencer. :)
Funny, I didn't know they are so inexpensive, I must be living under a rock. So, what about a homework, can you find under water one in this price range?
Be aware that those are not real CO2 detectors. They are actually extremely inaccurate and use a simple and cheap TVOC sensor which by design and specification are not meant to detect CO2 or measure in any way CO2 since they only output one signal. CO2 concentration is then extrapolated, calculated and faked through a chip. Proper CO2 detectors use what we call an NDIR CO2 sensors (nondispersive infrared sensor) which by themself are pricy. The component alone will cost ~30/40USD sometimes more depending the manufacturer. So any CO2 monitor out there retailing for less than 100/150USD or less will just be a scam and you can be warrantied that what you see on the screen of your cheap Chinese made device is no where close to the real concentration of CO2 in the air at any given time of measurement.
 
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@Hanuman So a bit like that guy who made £50 million during the Iraq wars selling £13 novelty golf ball finders as bomb detectors to security forces worldwide at £27,000 each. You've got to pity Trading Standards somewhat.
View attachment 188407
Thailand's Royal Army did purchase those at some point. I remember the scandal. The Army even tried BSing the public into believing this wass all legit and highly technologically advanced and people were too dumb to understand. It was brushed under the carpet following the backlash.
edit: typo
 
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For anyone wanting to have a proper CO2 sensor, this is the cheapest I've found. It's a DIY kit that will require some soldering and a bit of coding skills, but nothing too extreme.

There are other CO2 DIY projects out there but you need to source the component yourself and the monitor will end up costing more. For example:
OR

You can go and buy a commercial CO2 sensor for the modicum price of 229USD 🙂
You will probably find cheaper ones but nothing that is genuinely a CO2 sensor for sub 100USD
 
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Proper CO2 detectors use what we call an NDIR CO2 sensors (nondispersive infrared sensor) which by themself are pricy.
Hi @Hanuman
Would this product qualify?
It says, "With 2 different sensors: NDIR and TVOC provide 2 options for you, you can choose based on your requirement." And it costs CAD $36.

Amazon product ASIN B09N1JNLVV
It looks identical to what @sparkyweasel has.

3 IN 1 Portable LCD CO2 Meter Air Quality Carbon Dioxide Detector Tester Monitor | eBay
 
Hi @Hanuman
Would this product qualify?
It says, "With 2 different sensors: NDIR and TVOC provide 2 options for you, you can choose based on your requirement." And it costs CAD $36.

Amazon product ASIN B09N1JNLVV
It looks identical to what @sparkyweasel has.

3 IN 1 Portable LCD CO2 Meter Air Quality Carbon Dioxide Detector Tester Monitor | eBay
I'll be honest, I think that's a big fat lie. Considering the price it can only be a TVOC sensor. I wouldn't waste my money on that.
 
NDIR CO2 sensors (nondispersive infrared sensor) which by themself are pricy. The component alone will cost ~30/40USD
When I considered building a meter, the sensors were about £10 to buy just one at retail price. I imagine the large-scale Chinese makers can get them a lot cheaper than that.
Even the kit you linked to has the option of with or without the sensor, and the price difference is only $20.
 
When I considered building a meter, the sensors were about £10 to buy just one at retail price.
You see, el cheapo NDIR sensors like the one you just referred to are basically copies. Aliexperess is flooded by them. They are slow, inaccurate, unreliable. They usually have a detection range of 400-10000ppm or 0-5000ppm which technically is fine BUT with a very poor accuracy which can range from 100ppm to a 1000ppm 😬. There are not many companies producing quality NDIR. I suggest looking for Sensirion, Winsen, Cubic, Senseair. All produce quality, reliable sensors. Some are very expensive some very reasonable, but nothing like £10, that just wont happen and I wouldn't waste my money on those copies.
Even the kit you linked to has the option of with or without the sensor, and the price difference is only $20.
The component alone will cost ~30/40USD sometimes more depending the manufacturer.
The Kit I posted earlier is the cheapest you will find with a good quality sensor. They use the Senseair S8 sensor which retails for 25/30USD depending where you buy it from. AirGradient is able to get it for slightly lower because they buy it by the hundreds.
 
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For anyone wanting to have a proper CO2 sensor, this is the cheapest I've found. It's a DIY kit that will require some soldering and a bit of coding skills, but nothing too extreme.
I got myself this kit for 96USD. Got to say, seems pretty good. I added it in my bedroom last night before going to bed, and to no surprise the Co2 sky rocketed during sleeping hours. Maybe I should do something about this!!

Screen Shot 2022-08-22 at 15.52.54.jpg
 
Hi all,
Maybe I should do something about this!!
I would, 2000ppm is <"getting towards the limit for healthy living">. It will definitely cause drowsiness, and above 2000ppm aerial CO2 you get
........ Headaches, sleepiness and stagnant, stale, stuffy air. Poor concentration, loss of attention, increased heart rate and slight nausea may also be present.
Probably a silly question, but can you just open a window?

cheers Darrel
 
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Hi all,

I would, 2000ppm is <"getting towards the limit for healthy living">. It will definitely cause drowsiness and above 2000ppm aerial CO2 you get

Probaly a silly question but can you just open a window?

cheers Darrel
Yeah that won't be a good solution. Here in Thailand temps go in the 35-38C. We use air conditioning else it's just too hot to bear. But I definitely need to do something about this. Maybe ask my wife to sleep next room, although I anticipate that could be a cause for divorce. 😂
 
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