Cheap Electric Ph Monitors

[xxBarneyxx]

Have seen a few cheap electronic PH monitors on ebay for around £30. I'm assuming they cant be that great as all the PH monitoring equipment I have seen before was a LOT more expensive. Anyone used any of these or have any idea how accurate they are?

Not expecting them to be dead on but if they are reasonably close it might be worth getting one just for quick reference.

 

[CageUK]

I've got one (yes off of ebay) and it seems to be fine. It's quite tricky seeing how accurate it is against the liquid tests because numbers on a screen always look so much more convincing than trying to match up a colour in different kinds of light. If calibrated once in a while (I'm not sure how much they stray) then there shouldn't be a problem.

I leave mine hooked up to the tank permanently. It's interesting seeing though how actions you perform in the tank effect the way the optical lens works. For instance, turn the lights on or off and the readout goes crazy. It eventually settles down again to the previous reading (or close to).
You can also see in real time the effect of buffering... a real bonus!

 

[SkiFletch]

Well, I can't comment on what's available over there in the UK, but over here, I've had nothing but trouble with cheap pH meters. Technically I've only ever used them in a laboratory setting (not a marine aquaria one) but my lab experience with them has lead me to hate them. Things end up drifting, calibration takes forever and needs to be done routinely and the things just aren't worth it IMO. We ended up buying a very high-quality lab grade one here which is less troublesome for sure, but still not great.

 

[ben1987]

they are probably as good as digial thermometor off ebay....mine told me that my tap water was 38 degrees.