Odd readings. Can these numbers be correct?

[aquaman99]

Hello all,
I am testing the source water I was planning to use with the source salt. My salinity is 25.5SG I am using basically all Red Sea Reef Pro. I am also using Walmart brand distilled water.

My question is... Should I be getting a new test kit or new source water?

PH: 8.6
GH: Over 80. I stopped because it just kept getting darker red and the vile was completely full.
KH: 1

These number make no sense to me. How is my PH so high? Is my GH solution faulty? Is my KH faulty? They are all API. I bought the GH/KH combo. PH is from my freshwater kit and is usually spot on.

 

[aquaman99]

So after googling, It seems adding marine salt increases PH. I should have known that. Also the PH goes up at night. This explains why I tested a second jug of Great Value Distilled without salt and the PH was 7.6. But the GH and KH stayed the same. I am starting to think I have a faulty KH/GH test kit. Is there a better one out there other than API?

 

[Ly78]

Im not sure if the api gh/kh test kit combo is suitable for saltwater.

 

[aquaman99]

So...*rolls eyes*... I figured out my problem. I am bad with directions. I Just retested after properly reading AND following the directions and they test came out just fine. My tap water was: 18KH 22GH. My Great Value Distilled was: 7 on both. My saltwater mix was: 10KH but my GH still doesnt want to work for the salt water?

 

[Randy Holmes-Farley Verified Community Expert]

GH is not a useful measurement on seawater. It is a weird mix of magnesium, calcium, and strontium. The distilled water should not be 7 dKH. That is an error or bad water. 10 dKH after mixing salt into it says the 7 dKH was a test error and 10 dKH is fine.