ph probe gone bad???????

prsouthfl · #1 12/26/2007, 07:17 PM

i caliberated my ph probe and put it back in the tank it read 8.6 well i just turned on the maxiget to stir my kalk drip couple days later it said 7.6 know way as i tested it it came out 8.0 8.1 ish so i bought new solution at exotic aquatic and it was off a mile i used 7 and 10 so i was like cool never buy the big bottle of solution again as it went to waste so then i put it back in the tank and it says 7.8 again went back did the solution again and again got it perfect dip in the 10 reads 10.0 right away dip it in the 7 reads 7.0 right away then i put it back in the tank it reads 7.8 did the red sea test 8.0
went back to robs and andy came up with 8.0 too sooooo???
is the probe bad
its not even 2 yrs old never been dry
going to got to exotic aquatic tomm check it against there probes
any body ever had this prob
tia
paul

ReefWreak · #2 12/26/2007, 07:25 PM

You're supposed to replace pH probes every year, not every 2.

I was under the impression that a probe was bad if it would just constantly float around #s, not just calibrate wrong

jeffbrig · #3 12/26/2007, 09:32 PM

Sometimes other electronics can throw off the pH reading. I know the MJ powerheads I use to add and remove water from my sump throw the numbers out of whack significantly. FWIW, I've been using a pinpoint pH meter for a good 2 years now with the original probe. The instructions say replace it when you can no longer calibrate it, and mine has not reached that point yet.

prsouthfl · #4 12/26/2007, 10:09 PM

if i go betwween the 7 and 10 solution it off a point or so i could prob go back and forth all day i cant c replacing a probe once a year
anybody else??

saltwaterfishlover · #5 12/26/2007, 10:26 PM

Paul just for giggles take some water out of the tank into a cup or something and see how it reads.... maybe Jeff has an idea....

gasman059 · #6 12/26/2007, 10:45 PM

I believe my milwakee is done then it reads 5.0 in my reactor LOL

prsouthfl · #7 12/26/2007, 10:49 PM

it reads same same ina cup of water ill stop by tommorow andy

prsouthfl · #8 12/27/2007, 05:34 AM

how long u had the probe gasman?

gasman059 · #9 12/27/2007, 09:03 AM

Quote:

Originally posted by prsouthfl
how long u had the probe gasman?

bout 1 year ro so- its def me and not the probe.

prsouthfl · #10 12/27/2007, 11:05 PM

i think my meter is fine i just have an imbalance calcium iss at 450 dkh 10 every thing else is in check going to buffer the ph

jeffbrig · #11 12/27/2007, 11:16 PM

Quote:

Originally posted by prsouthfl
going to buffer the ph

Do some research about what you're adding before you throw in a pH "magic bullet". Most are alkalinity buffers, so they may cause other issues.

Fundamentally, pH is tied to alkalinity levels. With an alkalinity of 10dKh, I would not add any buffering compounds to the tank. If you have verified there is not a measurement problem, the most common cause of low pH when you have proper alkalinity is high indoor CO2.

prsouthfl · #12 12/27/2007, 11:26 PM

hmmmmm indoor co2
everything is fine if i didnt have a ph monitor i wouldnt be writeing this right now

i dont know ????????

jeffbrig · #13 12/28/2007, 10:47 AM

also, the quick and easy CO2 test is to take a cup of water, and put it outside with an air bubbler for a few hours. Then measure the pH, and if it's gone up, it was depressed due to high CO2.

FWIW, my tank settles to 7.8-7.9 overnight if I don't dose kalkwasser and/or 2-part (both of which consume excess CO2).