It's no wonder people have trouble and get confused

Buggsw

LifeTime Supporter
Apr 22, 2007
925
Arizona
#1
One source says one thing and another source says something totally different.

A local pool store stuck one of their dealer Pool Care guides in the bag with my new skimmer net. It's produced by Sun Pool & Spa Products. I was perusing through it while relaxing by the pool this evening.

I found this info odd, considering everything I've read in other pubs, forums and products. According to Sun:

TA should be maintained between 120 - 150 ppm. "To prevent pH from drifting or bouncing, the proper amount of acid buffers - or total alkalinity (TA) - must be maintained in the pool. Test weekly to maintain TA of 120-150 ppm. Low TA can result in pH bounce and fluctuations, as well as corrosiveness and staining. High TA can also cause pH to bounce and the possibility of coud water and scaling."

Most every other source I have on hand says TA should be maintained between 80 - 120.

Calcium Hardness is recommended by Sun to be:
200 - 250 for concrete pools
175 - 225 for vinyl pools

I'm doomed before I start with CH as Phoenix water is very hard and has a lot of CH. Other sources say CH is good between 200 - 500, yet others say 200 - 400.


The booklet says the pretty typical pH 7.2 - 7.6 and Free Chlorine 1 - 3 ppm. Nothing at all in the booklet about stabilizer/CYA.

Sooooo, what do you experts say about it. Are they right or wrong?
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#2
TA is fairly flexible. The ideal level depends on many things that vary from pool to pool and if you get it a little wrong nothing much tends to go wrong. If you are using trichlor tabs, which we don't reccomend, it is good to have TA on the high side. If you have a SWG then slightly lower levels of TA can help things.

CH can be zero in vinyl pools without a heater. CH levels for vinyl pools with a heater are not really clear, if your heater recommends something you might as well go with that. In a plaster pool it should be at least 200 and you should calculate your saturation index occasionally. Numbers in the 200 to 400 range are fine. CH can actually be almost anything as long as your saturation index is reasonable.

The ideal FC level completely depends on your CYA level, see the best guess chart.

I suggest a CYA level of 30 unless you have a SWG or a really really lot of sun. In those two cases CYA levels up to 80 seem alright. Others have different opinions on this one.
 

Buggsw

LifeTime Supporter
Apr 22, 2007
925
Arizona
#3
I see your point.

Sort of like there are many recipes for Chocolate Chip cookies or Margaritas. They can all be good in the end. :lol:
 
G
#4
Sun is a Chemtura company (along with Bioguard, Gardex, Omni, Hydrotech, Pooltime, and AquaChem). They are all major suppliers of stabilized chlorine which is acidic so running a higher TA will improve pH stability and keep your TA and pH from 'bottoming out' as quickly. (Pools that run on stabilized chlorine very rarely need acid but do need regular additions of baking soda, soda ash, and borax to keep the pH and TA up since they are both being constantly depleated.) Their company line is also to keep CYA below 200 ppm! :shock: . This way they can sell you a lot of algaecides and expensive borax to keep your pool from turning green when you have 200 ppm CYA and a 2 ppm FC level! If you are using an unstablized chloirne, which will be fairly pH neutral (alkaline when it goes in but has an acidic reaction when the chlorine is used up) then running a much lower TA will give better pH stability. The reason for their low CH numbers is to compensate for the higher TA.