$120 Chemical controller

CPO

Member
Sep 20, 2011
12
If I had an extra $120 to blow, I’d love to see how this would work as a cheep chemical controller for a pool.

Digital pH ORP Redox 2 in 1 Controller Monitor w/ Output Power Relay Control

I don’t understand the crazy costs of the controllers considering the electronics are so basic. This at least is reasonable!
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
18,072
Northern NJ
Maybe one of the folks who are homebrewing an automation system will give it a try. I doubt it will last long in an outdoor pool environment and wonder if any CYA will throw it off.
 

Bama Rambler

Mod Squad
TFP Expert
Bronze Supporter
LifeTime Supporter
Jun 22, 2009
24,020
SouthWest Alabama
CYA will definitely affect the readings. Another issue with it as that the adjustability is only -500mv to +500mv and you need to run about +600mv to +750mv for pool water.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
16,955
Tucson, AZ
screen grab.jpg

So the SELLER says it's NOT water resistant and can't be used outdoors AND the SELLER clearly doesn't understand how the probes work because, NO, you cannot store probes in DI water, that will degrade them. Most pH and ORP probes need a high molarity potassium ion solution (typically KCl) to be stored in because internal design of the probe is such that if you store in DI water the solution surrounding the platinum reference electrode will change over time (due to osmotic loss). Probes can be CLEANED with DI water (and sometime acid or bleach is necessary to remove contaminants) but they should always be STORED in a KCl solution.

Honestly, looks like a cheap setup that wouldn't last more than a year with the probes supplied. You still need to calibrate and clean it regularly (typical before and after each use) so I don't see how it would save any time. And, as always with ORP, one must understand that ORP does not always correlate well to FC in a pool water environment because of all the other confounding factors involved. So even if you get an ORP voltage, you need to calibrate it against a known FC measurement which requires a good DPD-FAS test anyway.

And, notice there are only two reviews and they both give 5 Stars....I wouldn't trust that at all....