Ca & Alk dosing during day and / or night?

[Pny]

With the modern dosers of today we can automatically split the dosing of both Alk and Calcium to many times a day. I've seen some claims that Ca dosing should be done during the light period and Alk dosing during the night period of the aquarium to minimize swings of pH and levels. Is this correct? During which periods do corals take up Ca and Alk? Maybe not all corals are the same?

 

[Mstanker]

Following this, I dose Alk Tues night. Maybe i dosed correct.

 

[nova65ss]

Honestly unless you are dosing a tremendous amount I don't feel it really matters enough to worry about.

 

[nova65ss]

But yes you are correct calcium during the day and alk towards the end of the light cycle.

 

[jeremy]

I have always dosed both during the day but alkalinity dosed top of the hour and calcium on the half hour. Dosed 8 different times during the day. I haven't noticed any ph swings while dosing.

 

[Randy Holmes-Farley Verified Community Expert]

There's no reason the calcium needs to be dosed at any particular time of the day. Whatever works for you, and with a doser on a timer, just about anything works equally well.

There is some advantage of dosing alk during the evening when the pH is lowest, to help boost the pH and keep the minimum a bit higher (or the day maximum a bit lower, depending on how you look at it).

There may also be a reason to dose some during the day if that is the time when more alkalinity is actually consumed.

Personally, I'd dose most at night unless the alk got below my target zone by the end of the light cycle.

Spacing them out so they are not adding at identical times is a good plan.