general hydroponics calibration solution issue

so i was calibrating my oakton "eco testr" tds pen using the hanna 1500ppm single use foil pouch because they were out of the Gh 1500ppm solution. it said my pen was roughly 200ppm over what it should be so i calibrated anyway.
today i picked up some of the GH calibration solution and when i use it to test my pen it read way over!!

has anyone had this issue? is the calibration solution pen specific?

shouldnt 1500ppm solution be universal? WTF??

I know this is an old thread. I am going to post here just for posterity's sake. Not all ppm reference solutions are created the same. The Oakton ppm meters need to be readjusted before using the General Hydroponics reference solution. You need to change the tds factor from .72 to .51. Here is a link to a video that shows how to do that.

http://www.youtube.com/watch?v=ayhlJiXmeQI

actually it turned out your suppose to use a different solution from oakton, so i bought it and everything worked out. thnx though

NEVER OUTGUNNED said:

actually it turned out your suppose to use a different solution from oakton, so i bought it and everything worked out. thnx though

Click to expand...

Never Outgunned can you let me know what solution you had to get from Oakton.
I'm having an issue trying to calibrate my Oakton Eco TDS Low pen with GH 1500 solution even after switching my tds factor to .510 I get an ER code on my screen.
I'd really appreciate it thanks in advance.