Low alkalinty

[Randy Holmes-Farley Verified Community Expert]

So I shouldn't do the water change and dose baking soda instead.?
And many thanks for the help

A water change is a far more expensive and time consuming approach, but its OK if you want to do it that way.

 

[seeky007]

A water change is a far more expensive and time consuming approach, but its OK if you want to do it that way.

I will do the baking soda and save the water change for next week.Many thanks

 

[Randy Holmes-Farley Verified Community Expert]

I will do the baking soda and save the water change for next week.Many thanks

You're welcome.

Here's a calculator to know how much to use:

https://reef.diesyst.com/chemcalc/chem_calc3.html

 

[exnisstech]

I'm not all that intelligent but to me it doesn't make sense that the tank would be that much lower than the fresh mix with nothing in the tank consuming alk. I set a new tank up a little over a month ago. Alk was 10.7 the day I filled. I tested yesterday and alk was 10.7 before doing the very first water change. Alk after water change 10.7 :thinking-face: no corals and nothing being dosed.

 

[Pod_01]

but to me it doesn't make sense that the tank would be that much lower than the fresh mix with nothing in the tank

That is perplexing to me as well…

Alk doesn’t evaporate…. so where did it go. From 12dkh to 5dkh…. and empty tank.

I do remember when I used RSCP salt the mixing instructions are somewhat complex and I always had precipitation….

Interesting regardless….

 

[Randy Holmes-Farley Verified Community Expert]

The only possible large sinks (if the alk measurement is real) is accumulation of high levels of nitrate, or precipitation onto calcium carbonate.

The latter is why I suggest boosting to 7 dKH, then monitoring it.

 

[seeky007]

That is perplexing to me as well…

Alk doesn’t evaporate…. so where did it go. From 12dkh to 5dkh…. and empty tank.

I do remember when I used RSCP salt the mixing instructions are somewhat complex and I always had precipitation….

Interesting regardless….

Yep it was somewhat puzzling.i had help from Randy who has sent me on the right path to fixing it.

 

[seeky007]

The only possible large sinks (if the alk measurement is real) is accumulation of high levels of nitrate, or precipitation onto calcium carbonate.

The latter is why I suggest boosting to 7 dKH, then monitoring it.

Just noticed this at the bottom of the sand bed?

 

[Randy Holmes-Farley Verified Community Expert]

That just looks like fine sand. Precipitating will harden some of the sand grains together. The fine ones will be especially prone to that, but those are buried. You might poke one small area and see if it moves freely.