Sunlight...natural dechlorination???

galleymore

Active member
Jul 7, 2010
28
I have a reasoable size pool (32'x32'x 5' deep) and need to drain it.
I have left it for about 3 weeks with no chemicals added, I have kept the pump going (to keep the water flowing) and have had constant sunshine (Caribbean) as well as heavy rains.....

I was told that it takes about a week to dechlorinate enough to allow draining into the ocean...?

Can anyone advise? :?:

Many thanks!!
 

Bama Rambler

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If you're draining it into the ocean I wouldn't think it'd need to dechlorinate at all. The order of magnitude difference would make the little bit of chlorine completely irrelevant.

However, a week should have the chlorine very near zero if not zero.
 

galleymore

Active member
Jul 7, 2010
28
Many thanks!

Based on that scenario.....would I be able to store water from the backwash into a contaier for use on the garden some days later?? Or could I just add it directly to my 4000gal rainwater tank and dilute it?

Thanks again!
 

Bama Rambler

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Most of us backwash our pool water directly on the lawn. I haven't noticed any ill effects. However we get about 60" of rain a year so in very dry areas things might be different.
 

solarboy

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Aug 1, 2010
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Europe
As long as it's not a salt water pool I don't see why not. I think if watering trees and shrubs you could probably get away with it straight out of the pool as on it's way to the plants roots it'll come across enough organics to use up all the chlorine. I wouldn't do it for too long in one place though.
 

chem geek

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Mar 28, 2007
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Don't forget that most water districts used to use chlorine (some now use monochloramine) at around 1 ppm or so and this was used for watering lawns, plants, etc.
 

galleymore

Active member
Jul 7, 2010
28
My Neighbor has a salt pool, is there anyway he can filter out the salt / backwash to use on the garden?

Someone said about filtering thru a sponge or secondary pool filter of some sorts|??
 

svenpup

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Nov 18, 2009
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Sacramento, CA
The salt is in solution and can't be "filtered" out. If a filter could remove salt then it would be impossible to have a salt water pool. The only way to remove it is with reverse osmosis which is probably not practical for this application.
 

galleymore

Active member
Jul 7, 2010
28
Many thanks for all the input..

i know we went slightly off thread but last comment on the intersting topic of re-using backwash water....!!

If my pal back washes (salt pool) into a small holding tank, then drains off the water thru a filter (DE?) to trap the debris...can the salt solution thats left be returned to the pool??

Thanks again!
 

JasonLion

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May 7, 2007
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I don't understand why you say "salt solution thats left". Is there any salt involved that wasn't in the pool in the first place?

Assuming that "salt solution" is a simple mistake and you actually meant the pool water left in the holding tank, then the answer depends on what kind of holding tank is being used. Less expensive holding tanks often allow metals and possibly other debris to get into the water. Unless the holding tank was designed for use with drinking water I would not put anything that was in it back into the pool.
 

galleymore

Active member
Jul 7, 2010
28
Sorry.....i have confused the issue!

Basically, if I backwash and send the BW water into a large plastic tank...could I then drain off the water thru a filter (cartridge?) to trap the dirt etc and leave the "salt solution / pool water" to flow back into the pool, which is now (in theory) free of debris & muck?


Sorry to be pain in the A***....I'll get the beers in.......!
 

Bama Rambler

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That certainly would work but it's a lot of trouble unless you're water restricted or water rates are extremely high where you are.

I guess my big question would be. Why not just replace the current filter with a cartridge filter and not have to worry about backwashing?