Does Alkalinity Consumption Rate Change

[Ocean’s Piece]

So I have been dosing for the past few months (no water changes) and I have never been able to identify and exact rate of Alk consumption in my tank. I’m unsure if this is just due to testing error or if this is because there’s not an exact rate of consumption. And note, this is with the same amount of corals and livestock.
Also, just to verify, does calcium consumption change? I have always had a weekly consumption of 10 ppm so I assume it doesn’t change, but while I’m on this thread, might as well verify.

 

[KrisReef]

If the consumers grow one would expect consumption to increase?

 

[shakacuz]

the more corals grow, the more alk is consumed.

 

[Ocean’s Piece]

If the consumers grow one would expect consumption to increase?

Ok that makes a lot more since. So basically yes to my question because it takes more as things grow, but no to the fact that consumption doesn’t just fluctuate for the hell of it

 

[DrMMI]

My alk rises from 12am - 6 am despite not dosing, so not only are my corals not uptaking alk, something must be releasing it back into the water. I have a feeling it's due to the overnight ph drop despite a reverse light refugium, recirculating CO2 scrubber, and dosing sodium hydroxide.

 

[Matt1997]

Consumption changes based on growth, if one of your large colonies goes dormant, if other parameters fall out of wack.

 

[Ocean’s Piece]

My alk rises from 12am - 6 am despite not dosing, so not only are my corals not uptaking alk, something must be releasing it back into the water. I have a feeling it's due to the overnight ph drop despite a reverse light refugium, recirculating CO2 scrubber, and dosing sodium hydroxide.

Yeah, I’m not a big chemistry buff, but mine does as well, which is normal. All my tests are done at the same time and temperature

 

[ColoredRock]

I thought this was interesting from this thread:

High Alk consumption

I have recently setup a new aquarium but moved my old rock and corals into this new tank. After about a week, my alk consumption increased but not calcium. Each day I am currently dosing - 20ml of Randys recipe (Backing Soda) 6ml of Calcium Chloride 3ml of Aquaforest mineral salts (was dosing...

www.reef2reef.com

High phosphate, like high magnesium and high organics and low alk and pH and calcium all contribute to lower likelihood of precipitating calcium carbonate.

Increasing nitrate (like in a cycling new tank) depletes alkalinity.

 

[Ocean’s Piece]

I thought this was interesting from this thread:

High Alk consumption

I have recently setup a new aquarium but moved my old rock and corals into this new tank. After about a week, my alk consumption increased but not calcium. Each day I am currently dosing - 20ml of Randys recipe (Backing Soda) 6ml of Calcium Chloride 3ml of Aquaforest mineral salts (was dosing...

www.reef2reef.com

This just gave my head a massive brain freeze…..WHAT!!…NITRATE?!?
Chemistry is so weird.

 

[ColoredRock]

This just gave my head a massive brain freeze…..WHAT!!…NITRATE?!?
Chemistry is so weird.

you and me too

 

[Randy Holmes-Farley Verified Community Expert]

Yeah, I’m not a big chemistry buff, but mine does as well, which is normal. All my tests are done at the same time and temperature

Most of the time, if folks see a rise in alk that repeats, it is due to even dosing and uneven demand as opposed to natural upswings in alk.

FWIW, alkalinity is consumed more during the daylight, and if you dose at night or 24/7, you may see alk fall during the day and rise at night (when dosing).