Tetra test kit

[Haddonisreef]

I test the Carbonate hardness w/ a tetra kit and got a 4 khreading how do i raise the kh to at least 8 to10?

 

[hawkfish21]

Baking soda.

 

[osprey77]

check your kit, that is really low,

 

[Zooid]

If your pH is stable I would definitely question the kit results. Otherwise I'd use a mix of washing soda and baking soda so the pH doesn't change too much.
I use a ratio of 6 parts baking soda to 1 part washing soda and I use the calculator from jdieck's site to figure out how much to add.

 

[Haddonisreef]

I retested this morning and it was 10 kh. Im not sure what happen, the only thing i did diff is use 10 ml instead of 5. Thanks for all that chimed in!