CO2 tuning - need help

Zeus.

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All test kits? All parameters? I know that my test kits give sufficiently accurate results. That'll do for me and I suspect would be perfectly acceptable for many other aquarists.

JPC

Each to their own OFC :thumbup:

But I embrace T Barrs EI dosing (no need for test kits) fully

However I did test my API test kit last week (had some time on my hands), with RO water, 5ppm NO3, 10ppm NO3 and 50ppm NO3, which I had made up, I must confess that I could see a difference in the range of [NO3] but they did not match the colour chart, they was close but not close enough. I could do with some more test tubes so I can run the tests with reference concentrations then use the colour change as a direct reference to the sample I'm checking.
 

foxfish

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The accuracy of home test kits is a much discussed subject on this forum, not so much of late but certainly two or three years ago, test kits were possibly the most debated theme outside of lighting and C02!
To be honest I never really absorbed the scientific reasons given but accepted the facts due to the facts being offered, were backed by very confident and experienced people.
As I remember it, most hobby kits are capable of measuring within reasonable limits but are often influenced by other chemicals that might be present in a aquarium.
Or in other words (maybe?) if you had a bucket of pure RO water and added a single element then that element might be detected quite accurately by the test kit but if you then added several other chemicals then the test results might well be effected and become inaccurate?
I am really not sure if that is a good analogy, maybe someone with a better grasp can explain it better.
 

jaypeecee

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As I remember it, most hobby kits are capable of measuring within reasonable limits but are often influenced by other chemicals that might be present in a aquarium.

Hi @foxfish

What you have said is one of the reasons why test kits may give inaccurate results. But, the $64,000 question (my chemistry master's favourite quote) is how inaccurate? Accuracy needs to be quantified. I would rather have a figure with +/-20% accuracy than no figure at all. I don't know of anyone who has done well-controlled scientific experiments to make the assertion that test kits are superfluous. But I'd be the first to sit up and listen to scientific facts. In fact, as I type this, I can think of a possible way. I know two professional chemists, one of whom runs an analytical chemistry laboratory. But I can't afford his prices! But, there is one other option and, dependent on price, I may be prepared to foot the bill.

In the meantime, if anyone knows of any scientifically-conducted test kit reviews, please bring them to our attention.

JPC
 

Zeus.

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if anyone knows of any scientifically-conducted test kit reviews

Well EI dosing doesn't need such test as the maths fits its purpose, dose in excess and 50% WC resets the tank, ferts are non limiting and toxins are kept with safe limits :angelic:

Its only worth doing a test if the result changes the path you would take or when the results take time it may modify the path when you get the results esp in medicine. So if the test are unreliable eg false positives etc treat for the worse case and watch your plants.
 

kilnakorr

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I see the thread has changed subject a bit, so just updating for any future readers.
you are not getting enough degassing over night if pH is 7.3. my suggestion is to invest and use a surface skimmer or at least try to increase surface agitation.
I have a decent amount of surface agitation, and run af skimmer 24/7.
can you fit an additonal inline solenoid to one? Unsure how this would effect the other if they were both regulated individually?
I could add another solonoid on one hose I think. If the tube and attachments can hold 20 psi pressure.

I've done a little tuning and monitoring. My PH today was 7.5, and reaching 6.8 is done in 2 hrs. Continues to drop to 6.6 but, inhabitants doesn't seem to care, however I only have shrimps and some ottos in there.
I might back of a bit on the CO2 at 6.7-6.8 and then start it 3 hours before lights on.
 

Andrew Butler

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I could add another solonoid on one hose I think. If the tube and attachments can hold 20 psi pressure
It doesn't look like there's a distributor in Denmark but a company called 'DMfit' make a variety of different fittings which should fit your requirements on the pipe fittings front and I've a stash of varying fittings here which I might be able to help you with but suggest getting in touch directly if you wish to explore this further and I'll see if I can help you out.
The solenoid I'm sure there will be one that suits your requirements but not something I've looked into properly before; I imagine someone has, somewhere though.
 

kilnakorr

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I little more tweaking and new ideas later and my CO2 is know 6.8 and stable.
I actually added a second powerhead for flow as I had a 'dead spot' in the tank. The types I'm using can output from 400 to 4000 liter per hour. They also have a light sensor that enables them to turn to lowest setting (400 lpr) when dark.
So the extra powerhead is angled to make more surface agitation when lights come on and increases offgasing of CO2. This seems to create the stable levels I'm looking for.
 

dw1305

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Hi all,
Or in other words (maybe?) if you had a bucket of pure RO water and added a single element then that element might be detected quite accurately by the test kit but if you then added several other chemicals then the test results might well be effected and become inaccurate?
That is pretty much it.

If you want an analogy it is like a colour photocopier, you can photocopy primary colours and get really good replication, but if you <"photocopy a bank note">* it can't replicate the different tones of brown, mauve, pale green etc.

cheers Darrel

*(allegedly)
 

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