PH rise to 13

[seanhorsay]

Hi reefers,

I get myself a new PH monitoring sys(APEX), but seems like the calibration is not that smooth? I don't really know confirm calibrated or not? The readings can fluctuated from 8.4+ to 13+ then go down 2 - 3 times within a day. My question is can fishes & corals tahan this unstable PH. I have no casualties, but the only problem is some corals not growing. But my duncans & efflatouria are spreading vigorously. Also, my forever problem is the undowndable NO3, which I doubt it contribute to hi PH rite? Or is my probe faulty?

Tank size - 1.5ft cube w/ sump

Ca - 440 ppm

Mg - 1380 ppm

KH - 10.5

Temp - 25 deg

Salinity - 1.025

PO4 - long time nvr measure, base on last time should be almost undetectable

NO3 - also long time nvr measure, almost give up.. base on last time should be 30 - 40

Pls help!!

[Martian]

You should get it calibrated. You can get the solution from C328. Water PH does not fluctuate like that.

[Martian]

PH meters normally does not come calibrated.

[Hon]

Make sure the pH probe is not near any pump or electro magnetic field. I have the same problem when I place my apex pH probe too near to a electrical field.

[Guest]

The PH shouldn't been fluctuating that much , check either if it is faulty or calibrated.

[seanhorsay]

Thx buddies here..

I definitely had calibrated it before using it. But the calibration results were not exactly what manual stated. That's why I'm not very sure that it's calibrated shui shui or not? I myself also felt that the probe might "up the lorry", as it shouldn't fluctuate that ridiculously. But when I took out the probe & dip it inside the used PH7.0 solution sachet, it give me almost accurate readings. Which makes me even more confuse! Come to think of that, might take bro Hon's suggestions as my probe position is very near to my Ehiem compact+5000 return pump.

[Nox]

u have to calibrate in ph 10 and ph 7.

and yes the pump will also affect the reading, tried myself yesterday, didn't believe at first