Milwaukee SMS122 Calibration solution

[FiberCon]

My SMS122 controller was shipped only with the pH 7.01 calibration buffer solution (it did not include the pH 4.01 solution.) A note was included saying that this solution is fine for most aquarium applications, but my water will be of a pH around 6.6 to 6.8 once I get it straighted out (right now it's around 6.2) and the note says that if used in an acidic situation that they will send you a pack of the 4.01 solution. I also noticed that in the instructions for calibrating the device that both the 7.01 and 4.01 solution is used, which makes the note confusing.

Question is, in my situation, do I need the 4.01 solution? I'm guessing that I don't since my pH is not far below 7, but I want to make sure.

Thanks...

[teedee]

Hi,

I have the same controler and usually calibrate it with pH 7.01 and pH 4.01 solution (I purchased those at a laboratory supply store). With pH 7.01 you set the offset and then adjust the slope with pH 4.01. That gives you the most accurate calibation. However, I have not seen any significant changes during the past three months in the slope, meaning that calibtrating at pH 7.01 is probably fine until the electrode starts to deteriorate.

Ciao
TD

[glass-gardens.com]

For freshwater aquarium applications, you do NOT want to calibrate the controller for 4.01 which is why they include the addedendum to the instructions and only include the 7.01 solution.

Calibrate the unit for 7.0 and you'll be fine. Quite frankly, I wish Milwaukee would simply change the instructions to alleviate this misunderstanding. Calibrating the 4.01 point widens the slope from what it would be with single point calibration and can lead to wider pH fluctuations than would be seen with single point calibration, and accuracy is best achieved by calibrating the unit as close to the set point normally used in the application.

[FiberCon]

Thanks Troy... I was going to email ya about this but I figured I'd post here so that others who might wonder the same thing would see the answer. (Which reminds me that I didn't search here for the answer before posting, which is very unlike me. Oh well.)

Thanks for the answer, thanks for the great service! The controller and regulator arrived today and I picked up a 5lbs CO2 tank so the only thing I'm waiting on is the tubing which I'm hoping will be here tomorrow (I guess I could go ahead and set it up with the tubing I have, but I might wait... Not sure yet.)

[corigan]

Originally Posted by glass-gardens.com

Quite frankly, I wish Milwaukee would simply change the instructions to alleviate this misunderstanding.

With the volume of buisness they seem to be doing I am suprised they haven't atleast added in a small paragraph about aquarium usage. I know if they would have changed the instructions they could have saved some time for one of their represenatives explaining the exact same calibration process as you had just described.

Matt

[glass-gardens.com]

Heh,

The corporate answer, a 3X5 card.

But I don't mind explaining, customer service is #1. I'm in the process of putting together a power point demonstration for the website and a CD for customers, explaining the whole system setup.

[cich]

Originally Posted by glass-gardens.com

But I don't mind explaining, customer service is #1.

I like you

--cich