Carbon Dosing Tropic Marin Bacto Balance

[14 foot reef]

Been looking into pH trends from my Apex lately and noticed something that happens exactly the same everyday. I dose 14,000ml of Kalk from a Avast marine K-2 Kalk stirrer from 10pm until 11:59 am the next day. My light cycle runs from 10:00am to 10:00pm with that kalk dosing schedule my pH stays very very flat except for one time period, that time period is from 12 noon to 3:00pm coincidentally the exact same time I carbon dose with the Tropic Marin Bacto Balance. Once the dosing stops at 3:00pm the pH bounces back to its flat line status of around 8.25

Does anyone else experience a decline in pH while carbon dosing? I've been watching this exact trend repeat itself for the last month.

Thanks in advance for any input on this.

 

[Randy Holmes-Farley Verified Community Expert]

Been looking into pH trends from my Apex lately and noticed something that happens exactly the same everyday. I dose 14,000ml of Kalk from a Avast marine K-2 Kalk stirrer from 10pm until 11:59 am the next day. My light cycle runs from 10:00am to 10:00pm with that kalk dosing schedule my pH stays very very flat except for one time period, that time period is from 12 noon to 3:00pm coincidentally the exact same time I carbon dose with the Tropic Marin Bacto Balance. Once the dosing stops at 3:00pm the pH bounces back to its flat line status of around 8.25

Does anyone else experience a decline in pH while carbon dosing? I've been watching this exact trend repeat itself for the last month.

Thanks in advance for any input on this.

Carbon dosing of any sort is expected to lower pH as the organics present are metabolized to CO2.

Some organics, such as acetic acid in vinegar, have the pH drop front loaded, but still ends up with the same total amount of pH lowering, although spreading it out can make it look like less.

 

[14 foot reef]

I can always count on you Randy for making sense of chemistry for me. Chemistry is my weakest knowledge in this hobby, but with all you have helped me with over the past decade or two, I'm getting a better & better understanding of it.

Thanks as always @Randy Holmes-Farley

 

[Randy Holmes-Farley Verified Community Expert]

You're welcome and thanks!

Happy reefing.

 

[haitian_reefer]

I dose the same and observed that as well, it appears to happen less with Tropic Marin vs Nopox. It was too much with nopox. I counter the drop in ph by dosing some alk manually to test

 

[air_run]

This is a great question for @SunnyX as he doses Kalk and uses TM Bacto Balance. This is why (per Randy's explanation) Sunny most likely doses Bacto Balance at the beginning of the light cycle? Maybe for ph reasons. I am curious though, why you would dose Bacto Balance in a 3 hour period instead of all at once? I only dose 1ml per day as I can't imagine dosing that little amount over a period of time. I'm just trying to figure this out as well.

 

[Randy Holmes-Farley Verified Community Expert]

This is a great question for @SunnyX as he doses Kalk and uses TM Bacto Balance. This is why (per Randy's explanation) Sunny most likely doses Bacto Balance at the beginning of the light cycle? Maybe for ph reasons. I am curious though, why you would dose Bacto Balance in a 3 hour period instead of all at once? I only dose 1ml per day as I can't imagine dosing that little amount over a period of time. I'm just trying to figure this out as well.

Reasons to spread out organic carbon dosing are the pH and O2 drops. Spreading those out reduces any possible issues from either one dropping too much at once.

When I was dosing vinegar manually once a day, I saturated it with calcium hydroxide (kalkwasser powder) to eliminate any immediate (or subsequent) pH drop.

later, I switched to dosing it spread over the light cycle by dosing pumps, and did not add the calcium hydroxide since spreading it out eliminated any substantial pH drop.

 

[air_run]

Reasons to spread out organic carbon dosing are the pH and O2 drops. Spreading those out reduces any possible issues from either one dropping too much at once.

When I was dosing vinegar manually once a day, I saturated it with calcium hydroxide (kalkwasser powder) to eliminate any immediate (or subsequent) pH drop.

later, I switched to dosing it spread over the light cycle by dosing pumps, and did not add the calcium hydroxide since spreading it out eliminated any substantial pH drop.

That makes sense. Thank you for the explanation Randy.