How is this even possible? Extremely low alk

[Baronen]

Hi guys. Got a Reefer 350 and I am stumped. I have been dosing all for reef (35 mls) daily which is the proportionate amount I was dosing in my Red Sea nano. This kept my aquarium in good condition and I stopped testing. These last two weeks I started testing my new tank (been up for about a month) because things just aren’t looking fully extended and was thrown off by the results

Salinity 35 ppt (refractometer)
Ca 410
Alk <5

How in the world can my alk be so low but calcium pretty solid. What is the best method to raise this without throwing everything off? Going to order another salifert kit just to make sure as well

 

[Garf]

I stopped testing

Why?

 

[Pistondog]

Test error may be the cause for low alk.
IF alk is low, a teaspoon of baking soda will raise dkh about 0.3 for that size tank.

 

[Baronen]

Why?

Because corals were growing extremely well. I’ve been testing my new tank is what I am saying. I have been dosing carbonate as well and just can’t get the alk up

 

[Randy Holmes-Farley Verified Community Expert]

The magic of chemistry allows it.

If alk was 8 dKH and calcium was 440 ppm, then you lost 3 dKH of alk, calcium would only be expected to drop about 20 ppm, and be above what you show.

That said, alk below 5 dKH is most often test error as it is hard to attain.

 

[Garf]

Alk <5

Doubtful

 

[shakacuz]

retest. buy new reagent. retest. dose accordingly.

 

[Oldreefer44]

Agree that is a testing error. I keep more than one brand of test kit for all major parameters. Reacting to a reading like yours can lead to problems worse than you had to start with.

 

[Baronen]

Retested with salifert and got 7 dkh. Are Red Sea kits known to be way off?

 

[Randy Holmes-Farley Verified Community Expert]

Retested with salifert and got 7 dkh. Are Red Sea kits known to be way off?

Not that I am aware of.