Yellowing/Spotting

[IVIars]

I figured i was wrong. I use lemon juice instead of the 4.01, it reads 2.1. Also maybe consider getting the General Hydro ph tester. Its $5-10 and good to double check your readings. But only use with clear or semi clear water or youll get the wrong reading. My meter needs a new probe since i left it out, the dial to calibrate it is turned all the way to one side and takes a few minutes to give me the ph reading. The ppm and ec still work good though

 

[Seamaiden]

It's probably because I'm a girl, but I find changing the probes to be a pain in the ass.

 

[tokeroo]

Oh... shiiiittt.. yeah, you've got to keep the probe/diode wet, but NOT with distilled water. I use the 4.01 calibration solution or one of the parts of my two-part cleaning solution. I'm also pretty anal about things like calibration, make note of temperature and always use the two-point calibration method. No point in spending the money or the time, IMO, even using a probe like that if you're not going to be absolutely certain it's accurate.

Alright, thank you so much (all of you) for helping here.

Seamaiden, it came with a little yellow "sponge" square to keep it moist. I have some storage solution, but never used it (since it didn't calibrate).

Do you think that by not keeping it moist I have ruined the pH probe? I can certainly moisten it up and all. The 4.01 and cleaning solutions should be here in a few days (prob tomorrow).

 

[Seamaiden]

Once it's dried out, to the best of my knowledge, it won't work properly again. You might want to contact Hanna to be absolutely certain, though.

I just fill up the cap with whatever I'm going to use to keep it moist, but again, never water and especially never distilled.

 

[tokeroo]

yeah I tried again 4 times last night. It reads the 7.01 in about 10-12 seconds. Then it waits ~5 minutes in the 4.01 and cuts off. I can't get it to read below 6.0. When it says it's calibrated, it reads the 7.0 at about 6.89 and reads the 4.01 at 6.25

Guess I need to contact HI about getting a replacement probe.

 

[Seamaiden]

That's sort of what happened to me (when I let a probe dry out) but it was backwards, just would never read the 7.01 solution and would shut off. And those readings are very off, you can't rely on that instrument as it stands right now at all.

In the meantime, just for your future benefit and "in case" I am going to suggest you also get yourself an aquarium water testing kit, and the one I will specifically suggest (in part because it's what I have on hand) is the Tetra Laborett Kit, which does tests for both fresh and salt water. It tests the following parameters: pH, NH3/4, NO2, NO3 (wait... does it test for NO3? no, not NO3, which bothers me in the aquatic sense)... so it's NH3/4, NO2, general and carbonate hardness, pH, and, with some calculations based on the hardness tests and pH you can also calculate the CO2 content of the test sample. Not that you'd want to, but you could.

Colorimetric titration kit and I've been able to get decent results using it. Once you try to test anything with Floranova Bloom in it, though, won't work, too thick and too dark to see color change.