Why my KH is so high?

[JohnMTL]

Hello I set up my tank in june, all was going well until last week. I did a 30% water change but my Kh wont seem to lower. Could it be the new white sand Ive put in? Estes' SPECTRASTONE
Ive also been using kalkwasser water to get my PH back to 8,1 as it keeps falling down to 7.8..7.6

Thank you!

 

[sde1500]

Now, I don't dose kalkwasser, but it is not for PH. Its for alk and calc. So dosing it for PH only is absolutely why kh is high.

 

[ReefNomad]

Estes spectrastone is colored, coated aquarium gravel... is that what you put in?

 

[Jon0807]

Now, I don't dose kalkwasser, but it is not for PH. Its for alk and calc. So dosing it for PH only is absolutely why kh is high.

^^ This. Kalk is used to raise alk and cal. The raise in PH is kind of a bonus. What is your KH measuring at?

 

[mcgyvr]

Stop worrying about your PH..
You didn't state what your KH was but because you are trying to mess with PH when you shouldn't be you are causing your KH to be too high..

Worry about KH and NOT PH..

Kalk is raising your KH.. and your calcium is probably elevated too..

So what is your KH?
Do you have lots of corals?