Low Calcium, Low Alkalinity, High Ph

[Ignotus_Peverell]

Hi guys,
I hit a stumper today and want some advice on the best way to handle it.

I want to get my Alk and Calcium up, but my PH is a little high. If I dose calcium bicarbonate I know ph will drop because of the buffer but dont want my ph to creep up after the fact.

Should I drop my PH first? Or just go with the calcium bicarbonate.

Thoughts

I normally just use purple up for adding calcium.

Salinity is 1.025
Alk is 7 Dkh
Calcium is 300
Ph is 8.3-8.4
Ammonia 0
Nitrate 0
Nitrite 0

Thanks for any advice
I.P.

 

[Rogued_Reefer]

Alk is not that low just do a water change

 

[Hemmdog]

Are you positive your salinity is 1.025? When is the last time you calibrated your refractometer?

 

[Rogued_Reefer]

Are you positive your salinity is 1.025? When is the last time you calibrated your refractometer?

Good question I didn’t think of that.

 

[Randy Holmes-Farley]

I don't understand what you are saying, since there is no such thing as calcium bicarbonate.

if you dose sodium bicarbonate, it will not raise pH when dosed. It will actually lower it a bit and is the way to go if you have pH where you want it or higher. Assuming you are not wanting to drive alk really high, the after the fact rise in pH is not a concern.

 

[Ignotus_Peverell]

Are you positive your salinity is 1.025? When is the last time you calibrated your refractometer?

Check it every time I use it.

 

[Ignotus_Peverell]

since there is no such thing as calcium bicarbonate.

You are correct I meant sodium bicarbonate. I want to push it up to an 8 Dkh.

I use a Kalkwaser mix in my ATO. However, my calcium and Alk just don't want to stay up.

And knowing sodium bicarbonate is a base it should push my ph up even higher but with chemistry and the buffer reaction, it isn't supposed too. (The one science I don't understand is Chemistry.) It always makes me nervous when I am on the edge and don't want to push my ph too much past 8.3.

 

[Randy Holmes-Farley]

You are correct I meant sodium bicarbonate. I want to push it up to an 8 Dkh.

I use a Kalkwaser mix in my ATO. However, my calcium and Alk just don't want to stay up.

And knowing sodium bicarbonate is a base it should push my ph up even higher but with chemistry and the buffer reaction, it isn't supposed too. (The one science I don't understand is Chemistry.) It always makes me nervous when I am on the edge and don't want to push my ph too much past 8.3.

Adding bicarbonate to seawater is theoretically expected to, and by measurement does, reduce pH, despite the fact that the solution before adding it will have a pH higher than the aquarium. The change from 7 to 8 dKH in terms of pH after stabilization is not enough to worry about.

 

[Ignotus_Peverell]

Thanks!