Brand new monitor calibrated without error. Fired up my recirculating DWC system (RO) a few days ago and pH was stable until suddenly the Bluelab shows pH bombing from 5.9 to 5.2 overnight. I crosschecked with two cheapo Amazon pH pens and both read 5.84-5.86. I don't think there's any chance pH swung this much in one night; roots have not hit the water and nutrient level is very low for seedling stage. Even stranger – all three pH meters are reading my tap water accurately. I'm embarrassed to admit this is my second Bluelab Guardian Monitor and both exhibited wild swings that don't make any sense. At a loss.
by pins_noodles
4 Comments
I have a ph controller from them and it’s been accurate so far, just had it for a few weeks. The cropsalt owners suggest them in their grow docs and say they have never had issues as long as they are calibrated. Maybe reach out and see what they say
You have to take emery cloth to the carbon tips on the EC sensor every week/month to prevent buildup and reading inaccuracy, your pH sensor reads in x.x units not ppm.
I moved onto Trolmaster Aqua x pro sensors but even those have issues of their own, I generally use an oakton EC pen to verify if I see swings
I only use Atlas Scientific. I don’t trust anything else I’ve touched.
Cleaning will depend on your reservoir. DTW salt based probably best but I recirculate and after a few weeks will have to clean some tips. Guardian + ph controller has served me well so far (I’m fairly new to hydro).
Edit: also as with any instrumentation cable; handling, bending, placing next to 120v pumps etc can affect the signal