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method to measure CO2 degas of tap water for WC in low tech

a1Matt

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Mine is in the living room too, oddly enough I quite like the sound, I find it quite relaxing :)
If I notice any differences I'll let you know.
 

Themuleous

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a1Matt said:
The driving force behind all this is that I want to make some water changes on my non CO2 tank as I have had some shrimp deaths and I think there is an ammonia spike\some toxicity in the water that water changes will help to remove.

Would it not be worth checking the NH3 levels with a test kit? Save you all this hassle? Shrimp could be dieing for a number of reasons.

a1Matt said:
As the tank is non CO2 if I carry out the water change with fresh tap water I will induce an outbreak of BBA in the tank due to the change in CO2 levels. I appreciate that water with CO2 at equilibrium with the air will not be an exact match of my tanks CO2 but I figure it will be as close as I can achieve.

Are you sure it'll induce BBA? I would be surprised if there is a massive difference in CO2 levels between a non-co2 tank and tap water. Perhaps do a quick pH/KH Co2 test to see what the difference is? Also, being a non-co2 tank I assume its low light so co2 level imbalances are less important. Similarly, if NH3 is in the tank, that is far more likely to cause BBA than any small change in co2 levels.

Just my thoughts :)

Sam
 

a1Matt

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Themuleous said:
Would it not be worth checking the NH3 levels with a test kit? Save you all this hassle? Shrimp could be dieing for a number of reasons.

The idea did cross my mind, but I thought that the ammonia spike could have come and gone by the time I had gone out and bought a test kit. So even if it showed no ammonia\nitrite that does not mean there wasn't a spike at some point. Plus on the day with the most shrimp fatalities I had time to change water or go and buy a kit, but not both. So figured the water change the best bet. In hindsight I think you are right and I should have tested sooner :oops: If problems continue (I think I am ove the worst of it now) then I will test.

Themuleous said:
Are you sure it'll induce BBA? I would be surprised if there is a massive difference in CO2 levels between a non-co2 tank and tap water. Perhaps do a quick pH/KH Co2 test to see what the difference is? Also, being a non-co2 tank I assume its low light so co2 level imbalances are less important. Similarly, if NH3 is in the tank, that is far more likely to cause BBA than any small change in co2 levels.

Just to calrify, when I say 'induce' I don't actually get 'new BBA' from a WC, rather I have some tufts already (usually on the gravel) and that BBA always spreads a bit more post water change. This is a consistent observation.
It is quite possible that I could be drawing a false correlation (like the "I added phosphates and I got algae" argument that persists).

I think (when I have time at home) I will do what you suggest and take some ph\kh measurements. Not sure they will be particularly accurate, but may offer some insight.

I initially started this thread just so that I could confirm when my tap water had degassed. It has turned up some info that has given me good food for thought, so I appreciate everyones input :D
 

Themuleous

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If I had to chose I would go with water changes over a test kit as well, if you get the test kit and find NH3 then its water changes anyway so might as well just skip the testing part! :lol: water changes shouldn't do any harm.

Glad it was useful :) out of interest, do you have your local water report? Mine says the tap water can contain NH3 (granted as very low levels) if the levels in your tap are higher that could be causing the BBA after a water change?

Sam
 

a1Matt

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I have the water report in a pile of papers at home. From memory anything unwanted in regards to the aquarium was in the range of parts per billion. I will dig it out and have a doublecheck.
 

ceg4048

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Themuleous said:
a1Matt said:
...Are you sure it'll induce BBA? I would be surprised if there is a massive difference in CO2 levels between a non-co2 tank and tap water. Perhaps do a quick pH/KH Co2 test to see what the difference is? Also, being a non-co2 tank I assume its low light so co2 level imbalances are less important. Similarly, if NH3 is in the tank, that is far more likely to cause BBA than any small change in co2 levels.
Sam prepare yourself for a surprise. There can be almost an order of magnitude difference between tap water and non-CO2 tank water. BBA responds immediately to CO2 fluctuations in a non-CO2 tank. Plants living in a non-CO2 injected environment have a very high density of Rubisco in the leaves. The massive influx of CO2 triggers a response to reduce the Rubisco production rate. This results in a CO2 shortfall if the CO2 level dissipates, which it does within a few hours after a water change. We should know by now that BBA responds to a CO2 instability, not necessarily to NH3 instability, and the observations of those who experience a BBA increase after a water change in a non injected tank supports this.

Cheers,
 

ceg4048

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Yep, an order of magnitude is a factor of 10. two orders of magnitude is a factor of a hundred.

A jump of 0.1 to 1.0 is just as bad as 1 to 10. They are both an order of magnitude difference and the plants response in manufacturing the Rubisco enzyme is just as disrupted.

Most are not aware of how important Rubisco is and how critical it's production is to Carbon uptake. This enzyme dependency is what make CO2 shortfalls so much more complicated than other nutrient shortfalls. It's a HUGE complicated molecule. It has binding sites, kind of like electromagnets, which attract and captures other specific molecules. On one side, a binding site captures either a CO2 or an O2 molecule. On the other side, a binding site captures a molecule known as Ribulose biphosphate (aka RuBP which is basically a sugar) Rubisco "ferries" these two captured molecules together during photosynthesis in order to carry out the process of "carbon fixation".

Plants sense the level of CO2 in the water and make specific adjustments to the Rubisco production. There must be a certain ratio of RuBP, CO2 and Rubisco for this ferry system and subsequent carbon fixation and food production to occur efficiently. It is a finely tuned system. When CO2 levels change, RuBP and Rubisco synthesis must also change. The complexity of the enzyme makes it very difficult for higher plants to adjust to rapidly changing CO2 concentration levels.

Algae have much less complicated systems so they adjust easily to changing or unstable conditions in the environment. This is the reason we see so much hair, BBA and staghorn. The more transient and unstable the system, the more these types proliferate. This is not to say that NH4 isn't a contributing factor, only that the dominant factor in these species reflect the difficulty we have with stabilizing adequate levels of CO2. Most species can adapt to low, long term CO2 shortages or to medium or high long term levels but fluctuating levels are a real problem.

Cheers,
 
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Themuleous said:
Are you sure it'll induce BBA? I would be surprised if there is a massive difference in CO2 levels between a non-co2 tank and tap water. Perhaps do a quick pH/KH Co2 test to see what the difference is? Also, being a non-co2 tank I assume its low light so co2 level imbalances are less important. Similarly, if NH3 is in the tank, that is far more likely to cause BBA than any small change in co2 levels.

Just my thoughts :)

Sam

i wandered about the co2 content in fresh tap water when i started my tank.
used the ph meter to measure fresh tap water and water that had been left out over night.
straight out of the tap ph was about 7.2
after 24 hours ph was 7.8

so it was coming out of my tap with nearly 15ppm co2 dropping to 4ppm overnight
(also out of interest i tested tank water after it had sat overnight to degass and got 7.5ph)
 
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