Co2-bacteria-breathing

boxfishpooalot

Active member
Randy I was thinking is Co2 that is created from bacteria blooms upon additions of sugar any different than Co2 from breathing in the air that enters the tank?

Reason I ask is because I noticed that algae grow much quicker with high nutrients with sugar additions. My thoughts were that Co2 produced from the bacteria was different or more bioavailable than Co2 in the air. When the ph is low from Co2 in the air with closed up windows, I dont notice algae grow any faster at the same ph. But with sugar its much faster with a drop of only .10ph units or the same ph with windows closed.

What else could be a reason for this if bacterial Co2 is not any different?
 
What else could be a reason for this if bacterial Co2 is not any different?

It's a matter of Thermo Kinetics, and geobiochemistry.

producing carbon dioxide through bacterial respiration seems like a good way to get carbon dioxide to the bottom of the tank (or a bad way of doing it, depending on how you feel about it). one of the things about carbon dioxide is that it dissolves into water about as quickly as it dissassociates from water, which makes it difficult to obtain high concentrations of carbon dioxide in solution.

A spike in bacterial growth should correspond to a spike in dissolved carbon dioxide levels within a tank; In other words, it's not that the carbon dioxide is different, per se, so much as wheere it's usually not.

since such a bacterial bloom would also have an associated trough in oxygen levels, have you noticed any change in sand bed fauna?
 
Hi Qcks,

This is a bb tank so there is no sand bed fauna. Im not sure im following you here. Are you saying its just a spike in Co2? If thats the case then algae should grow the same in normal Co2 at ph 8.2 . Keep in mind this tank has a large load of fish with too much orthophosphate and nitrate. :)

Well maybee algae growth is faster under higher Co2 levels. I just dont see it being limiting under normal Co2 levels.
 
Randy I was thinking is CO2 that is created from bacteria blooms upon additions of sugar any different than CO2 from breathing in the air that enters the tank?

It is the same, but perhaps can produce more of it than aeration. When nutrients are still very high even after the bacterial bloom, then some algae may benefit from the lowered pH and elevated CO2, as some use CO2 as their source of carbon.

Not until you get to the point where nitrate and/or phosphate becoming limiting to algae growth will you see a sugar/vodka/etc. addition help reduce algae.
 
Randy, if I add sugar to the water with ph of 8.2 it takes about 1 hour and the ph drops to 8.06 . This is from 1 1/2 tsp. Do you think the bacteria can utilize it that fast?
 
I should change my thoughts because its actually much faster. The ph drops .20ph units after only 10-15 minutes. Drops .01 as soon as sugar passes near the ph probe.10 seconds .02 drop.Does sugar have an effect on ph probes or do you suspect its bacteria ?

O yea one more thing. Sugar causes the skimmer to skimm out huge amounts of bacterial laden foam. It gets so thick and sticky that it does not collapse in the cup. What I did to solve it was added some olive oil to the cup. When the foam hits it it sinks into the water right away. Perfect just what i want.

What will happen if a tablespoon of olive oil gets in the tank?
 
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Contaminants in sugar would be responsible for any change in a few seconds. Beyond that, it is CO2 production. :)

Olive oil will pop bubbles in a skimmer under any circumstances, and might deter gas transfer across the air/water interface. If it coated an organism, it would be a concern, but a little olive oil is not likely a big deal.
 
Thanks. I thought to myself "do theese bacteria use up alkalinity, I better ask Randy?" fwiw the hair algae on my rock is turning white I think the bacteria is killing them.

Can you show me what forumula it is they would use with sugar? :)
 
C12H22O11 + 12 O2 ----> 12 CO2 + 11 H2O

How come I dont see anything relating to Nitrate uptake? Or phosphates? What I see is sugar + oxygen= Co2 and water released.
 
I think that algae use HCO3 not CO2 to photosynthesize, do I get that wrong?

Some algae use bicarbonate to make their own CO2 from it, and most can also use CO2 directly. :)

C12H22O11 + 12 O2 ----> 12 CO2 + 11 H2O

How come I dont see anything relating to Nitrate uptake? Or phosphates? What I see is sugar + oxygen= Co2 and water released.


That is just the equation for the metabolism of the sugar. They will make biomolecules to grow (making things that contain nitrogen and phosphorus such as DNA, proteins, etc), but there is no simple equation for that, aside from listing the relative proportions of different materials that there bodies are made of (which is not likely much different than algae, which I show in my nitrate article).


But, for example, if you ate the sugar, and you are not increasing in mass, you'd do just what that equation above shows. :)
 
Some algae use bicarbonate to make their own CO2 from it, and most can also use CO2 directly.

Can macro algae or marine plants use CO2 directly like algae do?

Thanks Randy. :)
 
Most microalgae primarily use CO2 directly but some can use HCO3- and most macroalgae primarily use HCO3- but can also use CO2 directly, am I right?

Thank you very much Randy.
Boxfish, I have to apologize for stealing your thread.
 
I'm not sure on the relative numbers of different species that can use HCO3-.

But in the table that I show in the article linked above, many species of macroalgae can, and perhaps a few cannot. How that extrapolates to all species I am not sure. I'm also not sure on the percentages for microalgae.
 
Boxfish, I have to apologize for stealing your thread.

Im not the kind of person to think like that :D No problem, besides its nice to have sombody else post in my thread besides me and Randy.

That is just the equation for the metabolism of the sugar. They will make biomolecules to grow (making things that contain nitrogen and phosphorus such as DNA, proteins, etc), but there is no simple equation for that, aside from listing the relative proportions of different materials that there bodies are made of (which is not likely much different than algae, which I show in my nitrate article).

Hmm well that leaves me stumped. I wonder why its said they will take nitrate from the water. Would a bacteria not metabolize organics to get at N,P? Fwiw the shared idea is that phosphate drops much quicker than nitrate does. And most posts that I have seen from people, experience phoshate drop well before nitrate does. I have not seen nitrate drop yet. And im out of phosphate tests....
 
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