Issue that may be related to calibration

[livinlifeinBKK]

Good morning, while you're online I thought I'd run something by you...I've been having issues with achieving the claimed calcium levels in AF Reef Salt and perhaps it has to do with my refractometer and salinity test pen I've been using...maybe they're giving me a false 35 ppt when in actuality it's more like 33 and that's why calcium is low even in newly mixed water. If this is the problem what would you recommend I use to get the best shot at accuracy? Even calibration seems to fail a lot of people from what I've read. It seems the most accurate are the hydrometers (leaving out the very pricey instruments I can't afford of course). What is your opinion on this? @Randy Holmes-Farley

 

[Randy Holmes-Farley Verified Community Expert]

Good morning, while you're online I thought I'd run something by you...I've been having issues with achieving the claimed calcium levels in AF Reef Salt and perhaps it has to do with my refractometer and salinity test pen I've been using...maybe they're giving me a false 35 ppt when in actuality it's more like 33 and that's why calcium is low even in newly mixed water. If this is the problem what would you recommend I use to get the best shot at accuracy? Even calibration seems to fail a lot of people from what I've read. It seems the most accurate are the hydrometers (leaving out the very pricey instruments I can't afford of course). What is your opinion on this? @Randy Holmes-Farley

M<y opinion is to check whatever devices you choose to use with a reliable standard.

If you have a scale, you can confirm any devices hobbyists use with one of the DIY fluids here:

Reef Aquarium Salinity: Homemade Calibration Standards by Randy Holmes-Farley - Reefkeeping.com

 

[livinlifeinBKK]

Thanks! I just read up on the article and it sounds like swing arm hydrometers would be the easiest to work with and it would be easy to simply draw a line on the true 35 PSU mark.
While I have you here, I had one more question I left in the forums a few hours ago about measuring pH in my nano. I was deciding between a Salifert test kit and an electronic pen that comes with the regeants to calibrate it and also comes with some litmus paper so you can roughly check to make sure the reading from the pen is in the ballpark at the very least cause as far as I know litmus paper doesn't lie. I went with the pen because I hate trying to match the always in between colors of a lot of those type test kits. Can I have your expert opinion regarding this choice? It's not a very professional testing pen admittedly but Salifert isn't so professional either and leaves plenty of room for measurement mistakes that would throw off the reading. I e even got a link here for the pen I ordered (lots of good reviews and several pics to scroll through since I doubt you can read Thai. It does use ATC btw...
If you think it's a bad idea I can always simply cancel the order. I can't afford one of the Hanna kits or any that level unfortunately.

https://shopee.co.th/product/17588883/6158802499?smtt=0.281183761-1650025429.9

 

[Randy Holmes-Farley Verified Community Expert]

Salifert is generally a reliable company, but pH test kits lack a way to verify proper function with one or more standards, while a true pH meter of any type that uses a pH electrode can always be checked for accuracy with standards.

 

[livinlifeinBKK]

Salifert is generally a reliable company, but pH test kits lack a way to verify proper function with one or more standards, while a true pH meter of any type that uses a pH electrode can always be checked for accuracy with standards.

So you think the pH test pen was the better choice since it can be checked for accuracy?

 

[Randy Holmes-Farley Verified Community Expert]

So you think the pH test pen was the better choice since it can be checked for accuracy?

It is checks out as accurate, yes.

 

[livinlifeinBKK]

It is checks out as accurate, yes.

Thanks for all the help this morning! (Nightime for me so I'll pick up the salt for calibrating for my salinity in the morning)