Swimming Pool Drain/Refill Questions

[StealthMonkey]

Hey guys. We're going to be draining and refilling our pool in the coming weeks. It is being done to repair the quartz, but it works out perfectly as the CYA is out of control due to using trichlor for two seasons (I now know better). I have a few questions on the matter.

1. Draining: My thought process is to let the chlorine drop over the last couple days so that the water getting drained is fairly unchlorinated. If I drain water onto my lawn with low chlorine and neutral-ish pH, will there be any problem? Is there a pH I should target?

2. Startup Chemistry: Is there anything I need to consider when starting up besides the standard Chlorine, pH, CYA, and Alkalinity? Is there a reason that any of these should be higher or lower than normal at the start? Or any specific order that I should address these in?

3. CYA Approach: Should I get standalone cyanuric acid and dump it in? Or should I just use trichlor tabs initially to raise the CYA levels? Oh, and what level should I initially aim for?

4. Gotchas: Anything I should know that I am missing? We've only had a pool for 1.5 years and never drained/refilled it. Is there anything I need to know that I haven't mentioned? Thanks!

 

[mknauss]

Welcome to the forum! My thoughts --

1. How high is your FC? If under 10 ppm, no big deal. pH not a big deal either. Salt could be, as you have been adding that with your use of Trichlor.
2. No. Start with chlorine and CYA. Dissolve your CYA while filling the pool. As it is winter, only target 30 ppm for now. Address pH as it needs to be and TA just let settle where it wants, unless rising pH is an issue.
3. Use CYA powder. Add to sock and dissolve while filling. I tie it to a bucket handle and run my hose into the bucket to help dissolve it. The pucks will take forever this time of year.
4. No real gotchas. I assume you are using a professional pool repair whom is taking responsibility for insuring the water table is low enough to drain the pool.

Take care.

- - - Updated - - -

One thing I forgot -- install a SWCG during this time! Get a IC40 - it will integrate with your pump and ET4. Best thing you will do. If you need the space remove the UV thing. It is not helping at all in an outdoor pool. The sun provides plenty of UV ---

 

[StealthMonkey]

Thanks for taking the time for the detailed response! Went and grabbed powered CYA today. Great tip on dispersing it, would never have thought of that. I also drove all around today and located the cheapest bleach I could find (I'm done with you trichlor!). I think I'm ready.

As for draining the water, I'll make sure FC gets very low over the last couple days. Sure, there will be some salt, but the pool has only be operation for 17 months, so I can't imagine the salinity is that high. According to the pool calculator, my 50lb bin of trichlor added ~230ppm of salt over the 17 months. Seems fine, right?

Definitely no water table issues here... all you'll fine is limestone. As for a SWG, believe me I am very tempted, but simply too scared of the talk of corrosion.

 

[Jimrahbe]

...As for a SWG, believe me I am very tempted, but simply too scared of the talk of corrosion.

sm,

Talk is cheap... I suggest you find someone that can actually prove that saltwater was the cause of any issues.

I have three saltwater pools and none of them show any signs of "corrosion"... The salt level in a saltwater pools is about the same as the salt level in your tears... About 1/10th of what is in the ocean.

Poor water maintenance and letting your pH get out of balance is the primary cause of most corrosion stories.

Thanks for posting,

Jim R.