How do I raise alkalinity without raising magnesium and calcium.

[dnprall]

Hello!

I'm using Tropic Marin All-for-Reef for dosing calcium/alkalinity and I know it has magnesium in it. Since the tank has been new, my alkalinity has been in the low 7's. When I started using the All-for-Reef per the bottle instructions, it seemed to swing calcium and magnesium quite high but not a big alkalinity increase so I've back off on dose and frequency.

At this time, I'm using small amounts of All-for-Reef and trying to keep calcium and magnesium from having large swings. Yesterday, my calcium was 379 and magnesium was 1310 and alkalinity was 7.4.

I'd like to increase the alkalinity to the high 7s/low 8s without increasing the calcium and magnesium with sharp swings. There is so much information on this website that I'm finding it hard to assimilate/synthesize what I should be doing.

Should I be using soda ash?

Thanks!

 

[Randy Holmes-Farley]

You can use baking soda/sodium bicarbonate, washing soda/soda ash/sodium carbonate, or sodium hydroxide. They are listed in oder of increasing pH boost per unit of alk added.

That said, you should want to boost calcium and I'd use All For Reef for any alk additions you need in the near term. Calcium and amgnesium wuill not bounce around too much.

 

[dnprall]

Perfect. That's what I need to know Randy. I'm comfortable with All-for-Reef. Very much appreciate your help.

Now on to figuring out the kinetics of my tank regarding phos dosing

 

[Icryhard]

You can use baking soda/sodium bicarbonate, washing soda/soda ash/sodium carbonate, or sodium hydroxide. They are listed in oder of increasing pH boost per unit of alk added.

That said, you should want to boost calcium and I'd use All For Reef for any alk additions you need in the near term. Calcium and amgnesium wuill not bounce around too much.

For some odd reason my magnesium is going up when adding baking soda. I honestly have no idea as to how, since there shouldn't be any magnesium present. Any other reason this could be happening? I do not add anything aside from amino and stuff like that for the corals.

 

[Randy Holmes-Farley]

For some odd reason my magnesium is going up when adding baking soda. I honestly have no idea as to how, since there shouldn't be any magnesium present. Any other reason this could be happening? I do not add anything aside from amino and stuff like that for the corals.

Test error is the only possibility, assuming you added sodium bicarbonate, and is very common for magnesium.

 

[Garf]

Or increasing salinity

 

[Randy Holmes-Farley]

Or increasing salinity

Yes.