Can bacteria use co2 for carbon? Interesting chain of events around nitrate, po4 and ph

[Kato]

Hi, so I had a chain of events in my tank that has gotten me thinking. So what happened was this:

1 A week ago I added a few Tropic Marin Reef balls (small balls that release bacteria over a period of time). I was starting another tank and thought I'd give the main one a few as well (actually underdosed a bit)
2 I noticed my PH would suddenly go up 0.2 to 8.4 (great) a few days later. While I was happy I was also wondering why. Didn't understand why this would suddenly happen. Perhaps the warmer weather though that should have less oxygen
3 A few days later I notice my chaeto grows slowly
4 I notice a torch died
5 Then I realise it must be missing nitrate and I test. And sure enough 0 (Hanna)
6 I also test PO4 now and its 0.8 (which is fine by me but on the higher side)
7 Ok so I dose nitrate, 6ppm in the afternoon
8 _Next morning_ I test po4 and its 0.009 (Hanna)
9 I can visually see the chaeto has gotten larger in 24 hours. So the added nitrate made it able to grow and also consume po4

So question is this. When I added the bacteria, did they consume all the co2 which drove up PH? I understand they probably ate the nitrate, though I had the impression they would consume oxygen and not co2.

Thoughts?

 

[Azedenkae]

Hi, so I had a chain of events in my tank that has gotten me thinking. So what happened was this:

1 A week ago I added a few Tropic Marin Reef balls (small balls that release bacteria over a period of time). I was starting another tank and thought I'd give the main one a few as well (actually underdosed a bit)
2 I noticed my PH would suddenly go up 0.2 to 8.4 (great) a few days later. While I was happy I was also wondering why. Didn't understand why this would suddenly happen. Perhaps the warmer weather though that should have less oxygen
3 A few days later I notice my chaeto grows slowly
4 I notice a torch died
5 Then I realise it must be missing nitrate and I test. And sure enough 0 (Hanna)
6 I also test PO4 now and its 0.8 (which is fine by me but on the higher side)
7 Ok so I dose nitrate, 6ppm in the afternoon
8 _Next morning_ I test po4 and its 0.009 (Hanna)
9 I can visually see the chaeto has gotten larger in 24 hours. So the added nitrate made it able to grow and also consume po4

So question is this. When I added the bacteria, did they consume all the co2 which drove up PH? I understand they probably ate the nitrate, though I had the impression they would consume oxygen and not co2.

Thoughts?

Some bacteria can consume carbon dioxide. A very well-known type are the cyanobacteria, which consumes carbon dioxide for the very familiar photosynthesis process. However, carbon dioxide fixation is not limited to photosynthesizers. A lot of nitrifiers are also capable of consuming carbon dioxide, incorporating the carbon into organic compounds - that is also why during the cycling process, adding fish food or a shrimp or whatever is not necessary, as the nitrifiers are fully capable of creating their own organic compounds rather than having to consume from the environment.

With that said, there is a lot of things that could have affected the pH. Chaeto for example, would of course consume carbon dioxide too. And measuring at different times of the day can see different pH.

I am also unsure what type of bacteria is released by the balls you mentioned. I tried to find 'Tropic Marine Reef balls' but for some reason can't even find the product.

 

[Kato]

Thanks a lot. Sorry it was fauna Marin:

Bacto Reef Balls - Fauna Marin

www.faunamarin.de

It’s just odd as the chaeto had been growing well before and ph was at 8.2 during the time. Then shortly after adding the bacteria, I’m now at 8.4.

Given I was at 0 nitrate perhaps the cyano was very close to materialize in full force.
Now that I doses nitrate ph has decreased a bit. Will see but I feel like I dodged a bullet catching nitrate bottoming.

 

[Randy Holmes-Farley]

What product exactly did you add? Link?

Nonphotosynthetic bacteria will not generally raise pH.

 

[Kato]

Bacto Reef Balls - Fauna Marin

www.faunamarin.de

 

[Kato]

US info: https://reefbuilders.com/2017/05/22/fauna-marin-bacto-reef-balls/

 

[Randy Holmes-Farley]

Ah, Fauna Marin, not Tropic Marin.

I do not think the bacteria or enzymes it contains are likely to raise pH, but I also do not know what else might be in it.

Coincidence and/or measurement variability are a likely, IMO.