Correct pool volume for shocking purposes

[kdubya815]

I am a newbie at the BBB method, but so far I have had much success with cleaning up my pool. However, now I am having a problem with a green tint in the deep end of the pool. I have being shocking it per the "how to shock your pool" instructions. My concern is that I am not using the correct volume for my pool. The pool store that put it in about 25 years ago (well before I owned it!) advised me that it was a 23,000 gallon pool. However, if I use the calculations on the Pool Calculator, it is closer to 30,000 gallons. Which one should I go by? It is an 18x36 grecian style inground pool, with the shallow end being about 3 1/2 ft deep and the deep end about 8 ft deep. Are my shocking efforts (and money!!) being wasted by using the pool company's advise?

Also, during the shocking process, should I vacuum and then brush (which seems to make a little more sense than brushing then vacuuming)?

Thank you so much for your help!!

 

[anonapersona]

Since you apparently have algae, your chlorine will be consumed by that right away so if you add bleach to get X ppm and get less than X, that just says some was consumed. But, you may be able to tell with acid additions or something like that. I eventually bumped up my pool volume to reflect what I got when I added chemicals. I suppose the extra volume may be in the spa and piping and waterfall.

 

[JasonLion]

A vinyl pool is never quite as large as it is calculated to be, the rounded corners and sloped sides always reduce the volume compared to the raw calculation. Still, the difference between 30,000 and 23,000 is larger than I would expect from the usual vinyl pool adjustments.

In the long run, you can adjust your pool volume estimates based on how the chemicals you add affect the pool. But that isn't going to help you right now.

The key to shocking is to keep raising FC based on frequent testing. Just at first you will be losing chlorine quickly, but as things progress, you can start compensating for any pool size estimate errors by adding more or less chlorine to reach your target level.

 

[frustratedpoolmom]

Is there no main drain in the bottom of the deep end?

Make sure you have at least one return pointed down towards the bottom there....anything you can do to improve circulation in the deep part will help the shocking process.

 

[kdubya815]

Thank you for all the quick responses! What I understand you all to say is that I need to check the FC even more frequently and adjust it as necessary based on the reading rather than the volume. Am I on the right track?

I do have a main drain at the bottom of the deep end, and the return jet is pointed down. Would it help speed up the process if I vacuumed it daily? I have brushed it several times since yesterday, but I have not vacuumed since I started shocking it.

Thank you for helping me!