Alk dropping but calcium stable?!?

[RaeOfSunshine]

hi any had a similar problem?
i use kalkassar and it all been stable until now... then suddenly my calc is fine but my alkalinity has been steadily dropping over the last few weeks.
about to start doing alk.
any advice?

 

[piranhaman00]

What is your pH?

 

[RaeOfSunshine]

What is your pH?

Oh is a bit low. It's 7.3 at the moment

 

[Bxr126]

I had the same issue. I figured out the GFO was slowly consuming ALK.

 

[piranhaman00]

Oh is a bit low. It's 7.3 at the moment

I am new to reef keeping so grain of salt. I think this could explain the low alk. If your dosing kalk how is your pH that low?

 

[RaeOfSunshine]

I am new to reef keeping so grain of salt. I think this could explain the low alk. If your dosing kalk how is your pH that low?

that is a solid question. im also on the new side. iv never had to do all the testing and water control my ex looked after it all lol

 

[RaeOfSunshine]

I had the same issue. I figured out the GFO was slowly consuming ALK.

i have a refugium sump but it could always be something down there thats messing it up

 

[Bxr126]

i have a refugium sump but it could always be something down there thats messing it up

If you are not running a GFO reactor then disregard my comment

 

[Saltyreef]

that is a solid question. im also on the new side. iv never had to do all the testing and water control my ex looked after it all lol

You should be testing daily to see what the consumption needs of your reef are.
Calcium, magnesium and alk. Kalkwasser wont keep these in check if you have any relative consumption from your coral stock.
Not testing and winging it are surefire methods of failure and life loss.

 

[W1ngz]

Oh is a bit low. It's 7.3 at the moment

7.3 is more than a 'bit' low. That will throw off the whole balance of the tank and start killing things. It's also low enough that it makes me wonder about the accuracy. It's more than likely an error.

It would be helpful if you posted a list of all of the tests and values you have available. Double check your testing procedures, and make sure you are reading the test correctly. Youtube has detailed videos of pretty well every test from every brand available.

 

[BeejReef]

You may want to re-post, or ask the mods to move this to the reef-chemistry forum.

I see you joined about a month ago. Brand new tank? Do you have corals and/or coraline?

Just be aware that alkalinity will drop a lot faster than calcium. New tanks and new reefers often say the tank is consuming alk but not calc. This is bc in daily testing, you'll see a drop in alkalinity, but alk would have to fall a full dkh (or even two) before you might detect a corresponding drop in calcium.

agree with others, 7.3 is crazy low ph. So low, it is almost certainly an error. You would have to try hard to drive ph that low, unless you're dosing something you haven't mentioned.