Chemistry Controllers Then and Now

In Blog, Controllers by Aaron Donohue

Back in the early to mid-90’s, chemistry controllers were seen as high priced items that only the big clubs could afford to purchase and maintain. The last few years have changed this perspective for many pool operators and indeed those who sign the checks for chemicals every month. Chemistry controllers are all but required for a commercial pool today due to the stability they provide for pool balance, and the reduction in man hours and chemical requirements that come from a stable pool/spa.


Initially though, chemistry controller technology was hit and miss.


The first pH sensors weren’t always “stable,” making pH harder to manage than modern variant. This resulted in a lot of time spent trying to get the controller reading the same as hand readings and increased pool operator frustration.


Even worse, the first attempts at ORP & PPM sensors fell flat on their face. A little bit of bad grounding, TDS a bit too high, a butterfly in china flapping its wings… all these things seemed to throw the probes out of calibration, requiring more time in front of the controller and more frustration.


It was no wonder, then, that hand measurements and manual chemical additions remained standard and chlorine delivery service was at an all-time high.


Fast forward a bit to 2013 and the picture is very different indeed. They are now very reliable, stable, and chock- full of options.  Capabilities include control of various pieces of pump room equipment, remote access from anywhere in the world, real time measurements of everything from pH and temperature to chlorine levels and line pressures. Because they log immense amounts of data can often create tracking graphs, they have become essential in determining chemistry balance trends and preempting them.


Controllers today can be so advanced that you really need to go into it like you do buying a car: determine what you want it to do, decide what functionality it MUST have, and then decide on what you are really willing to spend. Once  you have those three questions answered you can start your search for your controller.


There are plenty of options in the market to fit all needs and budgets, here are a few items I generally recommend considering when you are looking at a controller:


  • Do you need your chlorine automated? Or just pH?
  • Do you need multiple pump control? (i.e. pH, chlorine, and backup chlorine)
  • Do you need to be able to monitor the controller remotely?
  • Do you have multiple pools/spas?
  • Do you need flexibility to control other equipment? (i.e. chlorine generators, UV, Heaters, non-sanitation chemical pumps, backwash valves, etc.)
  • Do you know who you are buying from? (if not, ask their clients how good at supporting controllers they are)


The key thing is to purchase from a company who not only sells the equipment, but actually uses and supports it! If they just hang it on the wall and leave it to you to figure out, you simply won’t get the same results, and will likely be frustrated with your equipment. If you take your time and research your options thoroughly, you’re much more likely to end up with a controller that will satisfy your operational needs for years to come