My pool was installed with the Goldline by hayward ProLogic setup. There is an option to bypass the Sense and Dispence automation system. Has anyone had any experience with this system and if so what are the pros and cons?
I have the hayward automation system as well and would be curious to hear some real world reports on the "sense and dispense" as I would like to know if it would help keep my insane ph creep under control.
Yes, the PH feed system will keep PH under control quite well. There are other ways to eliminate, or at least greatly reduce, the acid demand even without a PH automation system, but they can take some effort to balance properly. The acid/CO2 feed simply takes care of it. It does add some extra maintenance tasks of it's own (refilling the acid/CO2 tank) but that is not too bad.
The ORP automation can be much more problematic. Sometimes ORP automation works well, but often enough it causes large fluctuations in the FC level and need to be turned off. Even when it does work, the tradeoffs are more significant, reducing the cell lifetime compared to using simple percentage based automation.
The Hayward manual recommends CO2. I didn't even know that was an option when it was put it. The pool builder who remodeled and put it in didn't tell me there was a choice. Since I've had some issues and have been talking to some Hayward people, someone there mentioned there were some issues with CO2. Other posts on TFP make it sound like CO2 isn't a terrific idea for residential for various reasons
CO2 systems are preferred by some vendors because they can never drive the PH so low that there is a risk to the pool. An acid feed system that gets stuck on can run the PH down to dangerous levels. This is a rare failure mode, they usually break so that acid is no longer being feed. And even if there is a problem you will probably notice it before the PH becomes dangerously low. Still, CO2 systems never have this problem. Continued CO2 injection will simply cause more CO2 outgassing and the PH will stabilize at a safe level regardless of how much CO2 is fed. There is also some minor personal risk when filling an acid tank. The risk of a CO2 tank exploding is far far lower, to the point where you can essentially ignore it.
Personally, I prefer acid feed. Acid is readily available and inexpensive. CO2 tanks are much less common and end up costing more. CO2 systems are also prone to improper installs, where much of the CO2 bubbles right out instead of dissolving in the water. And finally, acid lowers the TA, which tends to reduce the rate at which the PH rises. In a typical install the PH will get more and more stable over time. CO2 on the other hand does not affect the TA. If you combine a CO2 system with high TA fill water, your TA level will go up constantly and thus the amount of CO2 used will continue to increase until the system is overwhelmed and the PH goes up despite the CO2 feed system.
Don't misinterpret what I wrote. All of these problems are relatively minor/rare. Most people will be happy with either kind of system (assuming you can afford it).
The TA of the tap water in Austin (so I'm told) is 60, so rising TA would be a good thing in my case. With the massive amounts of aeration I constantly get (due to negative edge and skuppers), my TA is hard to keep maintained at a high enough level. This of course is a major contributor to my constantly rising PH issue. Based on what you're saying JasonLion, the Co2 might actually be a better solution for me. I'm not sure how long a C02 tank lasts or if it's feasible to go that route. I would still be interested to hear some of the other issues associated with that route. From a safety perspective, I would feel comfortable either way. In the VERY brief conversation I had with my pool builder, he indicated a preference for acid system, but didn't elaborate on why.