Alk after a water change

[Kmarshall168]

Just curious how quickly should alk change after a water change? Did a 20% water change this morning and my alk is the same as yesterday.

 

[Kmarshall168]

So just for information my alk was 6.6 yesterday and it is 6.6 today after the water change. I understand 6.6 is low and at this time I don't have a calcium or mag tester to see if those values are inversely high.

 

[Idech]

20% of what volume of water ? What’s the salinity of the salt you’re using ?

 

[Kmarshall168]

I guess it's only a 16% but it was 4 gallons of 24 gallon. And it's brightwell neo marine

 

[Lemons]

Should change instantly... once its mixed in.. 16% wont cause a large change unless your new SW is like 11dKH which is a bad idea lol

 

[The_Paradox]

Should change instantly... once its mixed in.. 16% wont cause a large change unless your new SW is like 11dKH which is a bad idea lol

Even with 11kh salt a 16% change would barely bring the tank over 7.

 

[Kmarshall168]

So more small water changes or say like a 50%

 

[Lemons]

Even with 11kh salt a 16% change would barely bring the tank over 7.

Yea i think their best option would be to do some 2part dosing to bring it back to acceptable levels

 

[Kmarshall168]

Yea i think their best option would be to do some 2part dosing to bring it back to acceptable levels

Feel like I would need to test calcium before that though right?

 

[The_Paradox]

Feel like I would need to test calcium before that though right?

You should but in a pinch can probably be skipped. Before you did anything though I would confirm 6.6 number as well as test fresh mixed saltwater. Any clue what your pH is?

 

[Lemons]

Second that,

And any precipitation by chance? Aka clumpy hard sand? Or weird hard dust??

 

[Kmarshall168]

8.2 at 77f

 

[Kmarshall168]

Second that,

And any precipitation by chance? Aka clumpy hard sand? Or weird hard dust??

Nope it was all powdery

 

[Kmarshall168]

What are the benefits of two part over all for reef or just kalkwasser

 

[Lemons]

Seems okay but in my experince i struggle to keep 8 if my dkh is lower then 7.8

 

[Lemons]

What are the benefits of two part over all for reef or just kalkwasser

More control, you only add alk or you only add CA

 

[Lemons]

All for reef is nice if things are in balance, but nature isnt perfect so eventually you will be thrown out of balance. Thats why i dont use a blanket dose like AFR

 

[Kmarshall168]

Seems okay but in my experince i struggle to keep 8 if my dkh is lower then 7.8

Interesting I tested both with a Hanna quick checker and api kit

 

[Lemons]

And kalkwasser is a good maintenance dosing additive, helps keep alk and CA in check but not reccomended to make changes with it

 

[Lemons]

Interesting I tested both with a Hanna quick checker and api kit

Hmmm i would check the big three,

Alk, Ca and mag then use 2part dosing to bring your tank back to more common levels. Slowy (cannot stresd that enough) like over the course or 2-3 weeks