pH confusion

Myka · #1 10-21-2011, 01:56 AM

Uhm...sounds like your calibration fluid is toast, or maybe you didn't use the right one seeing as you are exactly 5 points off? Did you use two calibration fluids (pH 7 and 10) or just pH 7?

Proteus · #2 10-21-2011, 02:04 AM

I tested with 7 and 4 I've alway used a Hight and low. I trust the chem test a little more. Could also be the probes are shot. I plan on taking a water sample in to the lfs just to be sure.

Proteus · #3 10-21-2011, 02:42 AM

The halides have been off for 45 minutes and Only t5 are on. I tested water again with both testers and now read 8.4.

Is it possible that the halides change the water on top that much.

mark · #4 10-21-2011, 03:12 AM

Quote:

Originally Posted by Titus99

The halides have been off for 45 minutes and Only t5 are on. I tested water again with both testers and now read 8.4.

Is it possible that the halides change the water on top that much.

probably more noise from the lights are effecting the probes than changing the water's pH

Myka · #5 10-21-2011, 03:50 AM

Quote:

Originally Posted by Titus99

I tested with 7 and 4 I've alway used a Hight and low. I trust the chem test a little more. Could also be the probes are shot. I plan on taking a water sample in to the lfs just to be sure.

When testing basic you need to use basic calibration fluids. You should be using 7 and 10. The 4 and 7 method is for alkaline (freshwater). I don't think the probes are dead...why would they both die at the same time and give the same reading? That's just weird. Considering you just calibrated both of them I think it is the calibration that is the issue. Even if you think 4 and 7 is ok to use, it is quite possible that the fluid you used is not accurate.