Salt Water Generator Pool Recommendations

For the below I want to acknowledge the tremendous amount of knowledge I gleaned from various web sites and forums across the Web. But foremost among these I have to say was Of course every pool is a bit different, whether it be the equipment you are using or the construction of the pool (cement, plaster, vinyl, etc.) or the environment your pool is in (indoor, outdoor, lots of debris can get into it, lots of sun exposure, etc.) so you need to tailor what you learn to your specific situation.

So the following is what I’ve synthesized to be ideal for myself and is still a bit of a work in progress but I think I’m asymptotically approaching the ideal for my situation.

My pool is relatively small (just under 11,000 Gallons), in ground and outside but protected from debris by being within a Lanai, sanitized using a Salt Water Generator (SWG) with massive filtration capacity due to having a DesJoyaux pump/filter which is efficient and quiet as my main cleaning system and a separate Jandy pump/filter which is primarily for sanitizing and heating the water. It’s also a vinyl pool for simplicity.

I use a blue bubble pool cover in the mid-fall through mid-spring to retain heat and do not close the pool in the winter even though it’s pretty much not usable from late November through early March.

Here is a letter I sent to my Pool folks after they emailed me with some concerns regarding my pool chemistry this year. Hitherto my pool was known to them for being pretty much perfectly chemically balanced all the time. There was a change in leadership and staff at the beginning of this season and I found that the chemistry readings from my weekly samples (yep, I said weekly) were all over the map. This told me that either the equipment being used was aged or faulty or that there was a training issue with the staff on using the sample testing equipment.

So I went ahead and ordered the TAYLOR TECHNOLOGIES INC K-2006 TEST KIT COMP CHLORINE FAS-DPD from Amazon (yes that’s a product link that pays me a tiny amount if you use it), sat down with the included booklet and spent a solid day studying just the kit. This made me realize how little I *really* knew about my pool’s chemistry and so I embarked on another month of research and then a few months of experimenting with my pool to get things to what I felt was the right place.

Anyway, this is what I sent to my pool folks, if you can make use of it or have questions or comments, please let me know.

After the premature failure of my salt cell (fortunately still in Warranty) and the somewhat erratic readings that the bioguard equipment was giving you this past year (not sure what happened as they have been very consistent prior to this), I did a *lot* of research into pool chemistry and determined that the recommendations that are being presented in the bioguard reports, while fine for a traditional chlorinated pool, are not suitable for a SWG pool.

In my opinion, two critical components for a SWG pool are the CYA readings and the Borate readings. These should be assessed with every sample.

If the CYA is too low, not only is the chlorine destroyed by sunlight too quickly, but the SWG itself is not nearly as efficient as at should be and will fail prematurely. This is what I believe happened to me. Higher CYA levels, combined with slightly elevated Salt levels, will keep my SWG functioning efficiently and without undue stress.

The Borate level is critical to stabilizing the PH which, by the nature of the chemistry involved has a tendency to increase significantly with rain fall. This was my biggest challenge in the past. Getting my Borate level up to a proper level now buffers my pool against tremendous PH swings.

Of course you have to be careful since the only way to remove too much CYA, Borate and Salt is to replace pool water so this is where care is required to *slowly* bring these to the proper levels while also balancing the other pool chemistry (since these will alter the PH levels).

Anyway, where I had “perfect” pool chemistry for the past 3 years for a generic pool, this year I believe I now have “proper” pool chemistry for a SWG pool. My Saturation index for the past month has been between -.04 and -.22 which is definitely acceptable.

I’d like to share my conclusions with you in case you are willing to share them with other SWG customers.

Item Range
Free CL 4.0-6.0
PH 7.4-7.6
Total ALK 60-80
Total Calcium Hardness 50-300 (not a typo)
CYA 70-80
Salt (depends on SWG) 3200-3700 (should be at high end of range for your SWG)
Borates 30-50
Saturation Index 0.5 – -0.3
Also, and this applies specifically to people who have a Fastlane (Endless Pools), The copper level needs to be tested every few weeks, monthly at the very least. While it is important to NOT use copper-based algaecides, I am finding that nearly all Zinc sacrificial anodes except those provided (at tremendous cost) by Endless Pools themselves have some level of Copper in them. This results in a black deposit on any stainless steel fittings in the pool. This is a cosmetic issue but it is distressing until you know what is causing it.

Hopefully this can help your other customers. The above is still a work in progress but I feel that these represent a consensus of the information I’ve gleaned from my research along with my own experience so far. With each passing month I have narrowed and refined the various ranges.
The ease with which I am able to balance my pool next year will be the proof in the pudding for me.


Posted under Pool

This post was written by Marc
on October 23, 2016 at 9:15 pm

How to calibrate the temperature on your iAqualink Unit


This was not obvious to me at all so I thought I would share it.

If you are finding your iAqualink unit is showing a temperature that is within 4 degrees higher or lower than your pool water actually is, you can go to Menu > System Setup > Temp Calibrate and get to a screen that looks like this one below.

Temperature Calibration Screen for iAqualink


I do not have a Spa so only the Pool is showing a valid temperature. The issue here is there is no obvious way to actually adjust the temperature and APPLY the change.

What you want to do is, with the pump running so the temperature is registering:

  • Click on the “Pool” button
  • Adjust the temperature using the arrow keys
  • Click the “Back” button until you reach the home screen again.

In about 15-20 seconds you should see the “Pool Temp” reading on the home screen adjust to the newly calibrated temperature.

This is completely counterintuitive since, to me, the “Back” button is equivalent to a “Cancel” key. “Take me out of here without changing anything”. It took over two months of going back and forth with Zodiac before I finally got a helpful person on their customer service line who could say something other than “You need to contact an authorized service company before we can do anything”.

Posted under Pool

This post was written by Marc
on July 22, 2015 at 8:11 pm