pH probe crazy after water change?

[jessezm]

Has anyone ever had their pH probe give crazy readings after a water change?

I changed 25% (60g) this morning and freaked out when I saw my ACjr reading 7.4, then 7.1, then 6.9, then 6.4!!!

Before doing anything drastic I got out two different test kits, which BOTH showed 8.3...

This hasn't happened before, and the only think I did differently this time was mixed the water for only 10 hours... It's Reef Crystals, and has been mixing and aerating all night, but usually I like to wait for several days before using new water (didn't have a choice this time, as I had to change the water before leaving for Atlanta tonight...)

All the animals look completely normal, and LPS/SPS/shrooms/Zoos all look normal

Any ideas? should I be worried as long as my test kits are reading OK? I tried my Calcium reactor probe and it also showed a low pH. Thanks!

 

[purplegorilla]

i had the same problem but it was because the battery was dying...

 

[jessezm]

hmmm... both my probes show the same reading, so I don't think it could be that (oh, and they don't use batteries, either...)

 

[FutureInterest]

When it jumps around like that you need to double check for stray voltage. Stray voltage will cause the probe to jump around like that. Hopefully the probe is just bad? I have a spare one if you want to check.

 

[jessezm]

Ooooh, I didn't think about that, Jin... I can't think of where stray voltage could be coming from all of a sudden.... Is there a way to test?

 

[FutureInterest]

Yah take some tank water out and put it in a container. Then put your probe in there. If the probe is still showing whacky numbers then you know its your probe or acjr acting up. If the number is 8.3 or wherever it should be according to your other tests, then its prolly stray voltage.

 

[jessezm]

Wow I just took my probe out and the glass is totally gone! what the...?

It was my probe--the other (calcium reactor) probe is now showing 8.1 (and that was a jump from 6.2 inside the reactor)

Ok, time for new probes all around!

 

[FutureInterest]

Just a theory, but perhaps the rapid temperature variance from the water change broke the glass?

 

[jessezm]

Temp was only off by .2 degrees...

 

[FutureInterest]

Unacceptable.

 

[jessezm]

and I tried so hard!