Need an Azimuth Check; CYA/Chlorine vs PoolMath

[tommyd123]

Hey All,

No real problems to report, but I do have a question on a disparity between the CYA/Chlorine Chart and PoolMath's TFP Recommendations:

For my CYA of 50, the CYA/Chlorine chart lists the upper limit of my range for chlorine at 6PPM, with a low of 4, but PoolMath with the TFP recommended numbers shows a max of 8 PPM. I have been following the CYA/Cl chart for the past few seasons, but had a few times this summer where the pool lost it's sparkle and I've had to raise the Cl to SLAM levels for a day or two(thats all it took to pass the SLAM). Was this due to my laziness, or not following the correct numbers?

Thanks!

 

[Catanzaro]

Your minimum FC is 4 based on CYA of 60. Your target is 6 daily (based on an average pool loosing 2 ppm per day). Do not know where the 8 comes from? (As I do not see that number). Do you keep records of your pool's behavior?

You mention that a few times this summer the pool lost is sparkle. Was this after heavy bather load or any other variables? How often do you brush and vacuum pool? How often do you backwash? Some people backwash every time they vacuum, which is not best for the sand filter. Please post full results, and any changes have occurred in your pool over the last month or so?

I personally work off a CYA of 50 and never allow FC to fall 5 at any given time (I do my best and so far so good). Additionally, I calculate my daily loss at 3 ppm, instead of 2 ppm. Every few days, I test with the test kit and either skip a day, or add less liquid chlorine.

There are so many variable to could affect water clarity. Do you have a heater? How often do you check PH and has it ever been out of range? How often to you test for FC & CC? How often for other tests, including CYA, CH and TA. Allowing the FC to slip below the minimum could be one reason. Other reasons could be not brushing the walls and floors and what you are seeing is dead algae on the surface.

Yesterday, I had children the pool with lotion. and in a few minutes after this post I will be testing FC and CC to determine if the levels are where they need to be. Sometimes, I even dose the pool after heavy usage of children, lotions, and run the filter all night long, and then check everything in the morning. Sometimes I will bring up my levels a few ppm to protect the FC from dropping below the minimums as the levels can always be adjusted later (Always safe to swim to shock level).

Keeping track of everything is important and making sure you liquid chlorine concentrations are calculated properly and storing the bleach somewhere dark and cool is also as important.

There was one day where 5 families were over with 9 small children, and in the course of the day I lost of 4.5 ppm. (Wow pool stores have you keeping levels at 3). In less than one day you would have no chlorine. Understanding your pool is important and that is what the TF-100 test kit does for you, (but you know that), and I have been using it more often than usual as August always seems the month where people get in trouble. Testing every 2-3 days during the week will tell the story on how your pool behaves.

Keep us posted!

 

[duraleigh]

Was this due to my laziness, or not following the correct numbers?

Yeah, I'm afraid we'll have to give you one for laziness. The precise, exact numbers don't matter that much so following one guide or the other won't affect your pool.

That you recognized what your pool was doing is the good thing and that you nipped it correctly is a VERY good thing.

 

[woodyp]

That minimum number is your bottom baseline to absolutely not fall below. The target number is gonna vary based on YOUR particular pools loss of FC daily.

 

[singingpond]

OP, despite several replies, I see no one has addressed your specific question about a discrepancy between numbers in PoolMath and in the chlorine/CYA chart. I think that the "target" number (6) in the chart is just in the middle of the range (4-8) given in PoolMath. In other words, the two tools show different angles on the same information.

 

[Catanzaro]

OP, despite several replies, I see no one has addressed your specific question about a discrepancy between numbers in PoolMath and in the chlorine/CYA chart. I think that the "target" number (6) in the chart is just in the middle of the "range" (4-8) given in PoolMath. In other words, the two tools show different angles on the same information.

Where is the range given in Pool Math? As I do not know this one. I did wonder in my thread where the 8 came from?

Also, it appears that 5 responses to this thread are no longer here. There is a total of 5 and with this one 6. Is everyone seeing the same 6 or 11? I checked with other computers and the same. Thank you.

 

[singingpond]

Where is the range given in Pool Math? As I do not know this one. I did wonder in my thread where the 8 came from?

Also, it appears that 5 responses to this thread are no longer here. There is a total of 5 and with this one 6. Is everyone seeing the same 6 or 11? I checked with other computers and the same. Thank you.

PoolMath actually uses the word "goal" for the 4-8 range - it appears both near the top, in the FC section, and down lower (in a section labeled "suggested FC levels") where it shows the different levels for SWG pools and normal pools.

I don't know what you mean about more replies to this thread that have disappeared (?) I didn't see any additional posts earlier.

 

[Catanzaro]

PoolMath actually uses the word "goal" for the 4-8 range - it appears both near the top, in the FC section, and down lower (in a section labeled "suggested FC levels") where it shows the different levels for SWG pools and normal pools.

I don't know what you mean about more replies to this thread that have disappeared (?) I didn't see any additional posts earlier.

I received e-mails for this thread from 08-24-2015 at 9:30 p.m. to 08-25-2015 to 1:30 p.m. Each time, I clicked on the link, it opened up the thread, but there was nothing there besides the 4 threads until the most recent posts. Maybe they were removed based on forum rules, etc. No biggie as I can read the posts.

I have everything downloaded to an e-mail created and use windows live. Everything is saved on a server so I can always reference back to anything discussed to refresh my memory.

 

[jblizzle]

The discussion about the public pool which did not address your question was split off for hijacking.

Focus on the minimum FC level. That is all that matters. You have to raise the FC daily high enough so you stay above the minimum.

 

[Catanzaro]

The discussion about the public pool which did not address your question was split off for hijacking.

Focus on the minimum FC level. That is all that matters. You have to raise the FC daily high enough so you stay above the minimum.

The thread was not mine. Just curious on why? I found the comments strange and unrelated, so the Hi-Jacking was appropriate. Thank you.