vacation suggestions

[ChuckD]

I've been thinking about this closing stuff, wondering about what's actually happening, and am starting to question parts of it. To wit: Shock and Poly-60.

It's understood that the Poly-60 will hit the Cl level hard (unknown how much it takes to knock X ppm Cl down to Y). But what's the reasoning behind the shock? If your water's shown no CC and no traces of algae for weeks previous. Cl will then serve no immediate purpose, and since it dissipates pretty quickly to zero, if it's not knocked out by the Poly-60 dose, it certainly serves no long term purpose.

So what's the point of the shock?

The only real long-term protection you can have is the algacide. It's starting to make sense to me that just a normal dose for a week or three absense, or a double dose for winterizing might be all that's needed.

Am I missing something?

[CarlD]

ChuckD,
You may be right, but my thinking is like this:
Pre-lim: Wait till pool is in the 60's or high 50's.

1. Shock the pool to get it virtually sterile
2. 1 quart of polyquat to inhibit algae growth. This, in 48 hours drives the FC to near 0.
3. Shock the pool again to kill any trace of anything.
4. Cover and close. The cover prevents UV from breaking down FC, and there should be CYA in the water too. The water's cold as a further inhibiter.

I open every spring to clear water, just dust and dirt on the bottom that the Blue Diamond clears with 3 or 4 cycles. I never have algae or a cloud in the spring.

Does the end of season shock matter? I don't know. Maybe not. But it ain't broke so I'm not fixin' it.

What's the risk? I use 6 gallons of bleach in the fall, and no algae in the spring. What if I don't use those 6 gallons and I have a bloom in the spring? It will cost me a lot more than 6 gallons of bleach to clear it.

I could roll the dice, but the upside is saving $10 on bleach, the downside is spending $30 or $40 extra to clear a bloom.