General Hardness and ALK test question

[Zoophile]

Hi all,

Hoping someone here can clear this up for me. I used a NutraFin titration-type test for KH to measure carbonate hardness, which I believe to be the same thing as alkalinity. My results were 116 mg/L, which the test booklet says is in an acceptable range.

My question is this: when I look up ALK parameters for reef tanks, there is always a low number given with no units. Is there a conversion for mg/L of carbonate ions to the ALK measurement everyone seems to be using?

Thanks for any help!

 

[fish tanked]

Your correct 116 alk is fine that is only slightly less than the average ocean value of 125ppm .
Your test measured alkalinity as ppm of CaCO3 , you most likely read either dKH or less frequently used meq/l which are lower numbers. You can see a conversion chart here http://ozreef.org/library/tables/alkalinity_conversion.html
Or you can just use this formula to convert to dKH
dkh = ppm CaCO3 divided by 17.86

 

[Zoophile]

Thanks so much! That's exactly the info I was looking for