Low Calcium High Alkalinity Issue

[EnemyAnenome]

Hello, I’m starting a new tank (25 gallon) and was wondering how I can decrease my alkalinity whilst increasing my calcium. I have nothing in the tank yet except live rock and sand. (Waiting to add any organism until I have more stability.) I know that my calcium an alkalinity are out of range. Any advice? Here are my parameters…


Temperature: 78* F (good)

pH: 8.1 (good)

Salinity: 1.025 (good)

Alkalinity: 14 dkh (decrease!!!)

Nitrate: 0

Phosphate: 0

Calcium: 320 ppm (increase)

 

[nereefpat]

You can increase Ca by adding calcium chloride. Since there isn't any livestock in the tank, you can decrease alk by adding a mineral acid. Muriatic acid is available and mostly safe if handled properly and added a few mLs at a time.

That being said...
To have 14 dKH and only 320 ppm Ca is a little odd. Some salt mixes have high alk, like Reef Crystals.
Have you added a 'buffer' of some sort to raise pH?
Are you sure on your salinity?
How are you testing alk and Ca?

 

[csturgis1989]

What kits are you using for testing? Is your salinity probe calibrated? What salt mix are you using?

 

[EnemyAnenome]

What kits are you using for testing? Is your salinity probe calibrated? What salt mix are you using?

Yes my probe is calibrated before use. I'll retry again. I am using coral pro salt.

 

[EnemyAnenome]

You can increase Ca by adding calcium chloride. Since there isn't any livestock in the tank, you can decrease alk by adding a mineral acid. Muriatic acid is available and mostly safe if handled properly and added a few mLs at a time.

That being said...
To have 14 dKH and only 320 ppm Ca is a little odd. Some salt mixes have high alk, like Reef Crystals.
Have you added a 'buffer' of some sort to raise pH?
Are you sure on your salinity?
How are you testing alk and Ca?

On a budget but I have been testing my parameters using API test kits. I'll redo the test again to see if I have the same results. I'm using coral pro salt mix as well.

 

[nereefpat]

On a budget but I have been testing my parameters using API test kits. I'll redo the test again to see if I have the same results. I'm using coral pro salt mix as well.

API's calcium and alk kits work just fine, in my experience. I believe the coral pro salt does have alk around 12 or so, but the Calcium reading is weird.

 

[csturgis1989]

Api alk tests have been notoriously inaccurate. I would recommend the salifert alk test kit. A new tank is probably not going to be using any alk or calcium so I’m guessing it is your mixing and testing.

 

[EnemyAnenome]

Did another test and the calcium came out to 360 ppm and the alkalinity again at 14 dkh. Weird. I'm guessing more water changes will stabilize my tank.

 

[billwill]

Time and living creatures are what are going to stabilize your tank. Salinity is the only thing you should be dialing in and maintaining when you start up a system. If not you're going to chase your tail trying to adjust one thing that then changes something else.

 

[EnemyAnenome]

Time and living creatures are what are going to stabilize your tank. Salinity is the only thing you should be dialing in and maintaining when you start up a system. If not you're going to chase your tail trying to adjust one thing that then changes something else.

Will do! I've been using my refractometer to check in on my salt. I'll just relax then on the other parameters.

 

[Randy Holmes-Farley Verified Community Expert]

Red Sea Coral pro will have more than enough calcium when mixed to 35 ppt salinity. I would not even be measuring calcium yet in a tank with no calcifying organisms.

 

[Randy Holmes-Farley Verified Community Expert]

Time and living creatures are what are going to stabilize your tank.

Why do you think creatures stabilize parameters?

 

[Dave Clark]

To have 14 dKH and only 320 ppm Ca is a little odd. Some salt mixes have high alk, like Reef Crystals.

For what it's worth ... I'm setting up a new tank and have the same issue ... 14 dKH and 340 ppm calcium, in my case.

I used Instant Ocean.

 

[homer1475]

Why do you think creatures stabilize parameters?

I think he meant they would use up some of the calcium, and alkalinity bringing better stability? Least thats how I took it.

 

[Randy Holmes-Farley Verified Community Expert]

For what it's worth ... I'm setting up a new tank and have the same issue ... 14 dKH and 340 ppm calcium, in my case.

I used Instant Ocean.

I'd be a bit surprised if that calcium level is accurate, but if it is, just add calcium chloride and let the alk fall.

 

[nereefpat]

For what it's worth ... I'm setting up a new tank and have the same issue ... 14 dKH and 340 ppm calcium, in my case.

I used Instant Ocean.

As Randy said, that Ca value is suspect.

Alk for regular IO should be in the 9-11 range, unless you added 'buffer''

 

[Dave Clark]

As Randy said, that Ca value is suspect.

Alk for regular IO should be in the 9-11 range, unless you added 'buffer''

I haven't added any buffer or any other kind of chemical. Maybe a bad API Master Reef test kit? Thank you.

 

[nereefpat]

I haven't added any buffer or any other kind of chemical. Maybe a bad API Master Reef test kit? Thank you.

I haven't added any buffer or any other kind of chemical. Maybe a bad API Master Reef test kit? Thank you.

API's alkalinity kit is fine. Regular IO, purple bucket, not orange right?

 

[Dave Clark]

API's alkalinity kit is fine. Regular IO, purple bucket, not orange right?

Right.

But … ugh … rechecked my notes, my alkalinity was 11 dKH, not 14. Not sure what I was thinking. Sorry.