I do not get this

[Lasse]

Hi

I thought I know most things affecting the pH in a reef aquarium with a very heavy photosynthesis - but I do not

Look at this chart. You see a daily variation of the pH depending on photosynthesis and CO2 production/consumption. From 20:00 in the evening to noon the next day I´m dosing the Core 7 3A and 3B. Around 16:00 the 19/6 I discover that I had low calcium levels - around 340 ppm. I decide to use CaCl *2 H2O in order to adjust the levels. The normal dose of core 7 (1,2 3A and 3B) continue. I dose an onetime dose directly and set one of my dosing pumps to dose 32 times a day and with a amount that will rise the Ca level with 40 ppm in 7 days. and look at the graph - what´s happen. The only change is the dosing of CaCl*2H2O. Light is the same. Can it be a fast calcification that alter the pH? Not more CO2 in the room. I have normally 400 - 800 ppm CO2 in my air - these last days - no higher than 640 ppm

Yesterday KH 8.6 - today 8. Calcium - when I discover the problem 330 - today 350 ppm


Sincerely Lasse

 

[DarkSky]

Did you have a bunch of guests over?

 

[MnFish1]

Hi

I thought I know most things affecting the pH in a reef aquarium with a very heavy photosynthesis - but I do not

Look at this chart. You see a daily variation of the pH depending on photosynthesis and CO2 production/consumption. From 20:00 in the evening to noon the next day I´m dosing the Core 7 3A and 3B. Around 16:00 the 19/6 I discover that I had low calcium levels - around 340 ppm. I decide to use CaCl *2 H2O in order to adjust the levels. The normal dose of core 7 (1,2 3A and 3B) continue. I dose an onetime dose directly and set one of my dosing pumps to dose 32 times a day and with a amount that will rise the Ca level with 40 ppm in 7 days. and look at the graph - what´s happen. The only change is the dosing of CaCl*2H2O. Light is the same. Can it be a fast calcification that alter the pH? Not more CO2 in the room. I have normally 400 - 800 ppm CO2 in my air - these last days - no higher than 640 ppm

Yesterday KH 8.6 - today 8. Calcium - when I discover the problem 330 - today 350 ppm


Sincerely Lasse

https://www.liveaquaria.com/article/98/?aid=98

 

[Lasse]

Did you have a bunch of guests over?

Nope - as I state

I have normally 400 - 800 ppm CO2 in my air - these last days - no higher than 640 ppm

I measure my CO2 levels

​

Sincerely Lasse

 

[Lasse]

https://www.liveaquaria.com/article/98/?aid=98

Yes but my PH is affected very much - seems to be much CO2 in the water - but alkalinity was going down to 8 and normally - without dosing CaCl - i will have the same swing of around 0.3 to 0.4. if I have a KH at 8

Sincerely Lasse

 

[MnFish1]

Yes but my PH is affected very much - seems to be much CO2 in the water - but alkalinity was going down to 8 and normally - without dosing CaCl - i will have the same swing of around 0.3 to 0.4. if I have a KH at 8

Sincerely Lasse

Correct me if im wrong - but the article says that adding Cacl2 too quickly can deplete the buffering capacity. To me this would suggest that with the same level of CO2, the Ph would be lower (depending on how much it was depleted). Could it be an error in one of your measurements? I was also wondering - how did your Ca get so low - could that test have been an error?

 

[Gareth elliott]

Can you use a ph/kh table to determine dissolved co2 in a marine tank?
I dont really have any insight, just what ive used to determine if i am at my target 30ppm for my planted.

 

[Lasse]

Correct me if im wrong - but the article says that adding Cacl2 too quickly can deplete the buffering capacity. To me this would suggest that with the same level of CO2, the Ph would be lower (depending on how much it was depleted). Could it be an error in one of your measurements? I was also wondering - how did your Ca get so low - could that test have been an error?

KH was depleted 0.6 - from 8.6 to 8.0. My variation of 0.4 of PH is normal when I have KH 8. And you can see the pH drop when I added CaCL. This should not happen if there is not any other mechanisms in this. I have shout down my dosing of CaCL for tomorrow - we will see if there is any change in behaviour . Reason why going down - missed that a tube was lose and miss use of Core 7

You know - even the Sun has patches


Sincerely Lasse

 

[Lasse]

Can you use a ph/kh table to determine dissolved co2 in a marine tank?
I dont really have any insight, just what ive used to determine if i am at my target 30ppm for my planted.

Not in the same way as in low pH planted tanks I think.

Sincerely Lasse

 

[Dr. Dendrostein]

Your a night owl. As regards answer, I'm stumped. You got me on that one. Over my head. We need a chemist/reefer.

 

[BZOFIQ]

Nope - as I state


I measure my CO2 levels

​

Sincerely Lasse

What equipment do you use to take these measurements? What does INNE stand for? (other?)

 

[Lasse]

Inne = indoors
Netamo wetherstation

Sincerely Lasse

 

[Dr. Dendrostein]

Lasse, does dry bulb and wet bulb temperatures indoor effect reef tanks?

 

[Dr. Dendrostein]

While we're waiting for Randy, now I'm curious with your INNE, it must do relative humidity, indoor temperatures, dry/wet bulb?, wonder what else?

 

[Randy Holmes-Farley]

When the alk drops due to calcification, there are two effects that lower pH. I do not know if this was your issue, or something else, or test errors.

When a coral takes up Co3--, le Chatlier's Principle says the bicarbonate/carbonate equilibrium will shift to replace it, and that process produces H+ and lowers pH:

HCO3-- <--->>> CO3-- + H+


Also, the higher the total alkalinity, the higher the ph will be at a given CO2 level. So as the alk drops, the pH will drop if everything else is basically unchanged.

 

[Lasse]

Indoors

​

Here do you find me - Ute - outdoors

​

Sincerely Lasse

 

[Dr. Dendrostein]

When the alk drops due to calcification, there are two effects that lower pH. I do not know if this was your issue, or something else, or test errors.

When a coral takes up Co3--, le Chatlier's Principle says the bicarbonate/carbonate equilibrium will shift to replace it, and that process produces H+ and lowers pH:

HCO3-- <--->>> CO3-- + H+


Also, the higher the total alkalinity, the higher the ph will be at a given CO2 level. So as the alk drops, the pH will drop if everything else is basically unchanged.

Thanks for answer(s). This way over my head. I do dream sometime, wish I was a chemical engineer. I do enjoy chemistry. Thanks again.

 

[Lasse]

When the alk drops due to calcification, there are two effects that lower pH. I do not know if this was your issue, or something else, or test errors.

When a coral takes up Co3--, le Chatlier's Principle says the bicarbonate/carbonate equilibrium will shift to replace it, and that process produces H+ and lowers pH:

HCO3-- <--->>> CO3-- + H+


Also, the higher the total alkalinity, the higher the ph will be at a given CO2 level. So as the alk drops, the pH will drop if everything else is basically unchanged.

Thank you - have never seen this before but from now and to tomorrow night - I will not dose any CaCL to the tank. I will calibrate the pH meter tomorrow too. it looks like the photosynthesis not have driven up the pH as usual

Sincerely Lasse

 

[Randy Holmes-Farley]

Lasse, does dry bulb and wet bulb temperatures indoor effect reef tanks?

Effects evaporation, but not CO2 or pH (unless pH is tied to evaporation by something like limewater in an ATO).

 

[Dr. Dendrostein]

Indoors

​

Here do you find me - Ute - outdoors

​

Sincerely Lasse

Come on, do you have a drone too?