FAS-DPD Testing for the colorblind

[waterbear]

Many moons ago when I was in high school (I was wearing bell bottom jeans and had long hair!) I was in a special advanced science program and spent half the day at the Univeristy of Miami School of Marine and Atmospheric Science doing "reseach" in oceanagraphic physical chemistry. I was actually an unpaid lab assistant! I spent many hours calibarating pH meters(I even had to mix my own buffers and standards!) and I never wish to repeat that experience again in my life! I did get to do titrations to determine the precipitation of calcium carbonate (you all know it as "scale") from seawater and simple seawater like solutions. Did you know that high concentrations of phosphates cause the precipitation of the aragonite form rather than the calcite form? Hope this is not too off topic but apoolman's post brought back the memories!

[ScottS]

I spent many hours calibarating pH meters(I even had to mix my own buffers and standards!) and I never wish to repeat that experience again in my life!

Haha I've never done and I definitely take your word for it. Thanks for understanding

[PoolDoc]

Waterbear;

You need to work up an account of the calibration process that you can post everytime somebody starts dreaming about all-electronic testing. People get tired of hearing it from me, but they also forget that 'all-electronic' testing STILL has to have a wet-end somewhere!

I was gullible enough, years ago, to sail to the that 'all-electronic' siren song, wasting a lot of time and money on the way.

I finally threw out some old boxes of useless (!) Hanna ORP, pH and TDS meters, replacement electrodes of various types, and several flavors of ORP and pH controllers. Some ORP controllers have a valid place in commercial operation . . . but Hanna Instruments' products? -- faugh, a plague upon them!

Ben

[waterbear]

Waterbear;

You need to work up an account of the calibration process that you can post everytime somebody starts dreaming about all-electronic testing.

Ben

And will you then pay for the psychonalysis I will need after dredging up repressed tramatic teenage memories after all these years?
Suffice to say it is an exercise in bordom, frustration, and tedium (and then you screw it up and have to do it over again!) Oh, did I add that the probes are delicate and they do need to be replaced from time to time, like when you accidently tap them against something (like the 3 beakers with the calibartion standards) and they break? I'd rather fill a vial with water, add a few drops of indicator, and look at the color. Much faster and easier. In my previous post I said that I have used them in salt water aquariums (and not for routine testing--I use a drop based pH test for that). I have NEVER used one in my pool!
Oh yeah, I forgot, the probes need to be stored wet or they become useless and need to be replaced!
Oh yeah, I forght, the probes wear out after a while and need to be replaced!
Oh yeah, I forgot, the buffers need to be mixed up fresh with deionized water (4-column) daily!
I could go one but it's just becoming too painful! I think I'll just curl up in a dark corner in a fetal position now.

[CarlD]

ScottS:

I think you are better off using the "cultivate girlfriend" method. $1000 of equipment buys a lot of dinners, movies, flowers--and think of the fringe benefits

[ScottS]

ScottS:

I think you are better off using the "cultivate girlfriend" method. $1000 of equipment buys a lot of dinners, movies, flowers--and think of the fringe benefits

HAHA Carl you are absolutely correct. Fortunately for me it doesn't take near that much to make her happy It's a win win situation.