Reuse backwash?

cfclay

Well-known member
Apr 24, 2010
233
Lexington,Ky
Howdy folks, it's been awhile. I didn't want to unroll my 100 ft backwash hose and I had an idea. I had this old doughboy sand filter housing and I thought I would see if I could put the backwash water in there and let the junk settle to the bottom and see if I could pump the good water ( after settling for a day) at the top back into the pool through the skimmer. Is that crazy, would that be a dumb idea?
 

woodyp

Mod Squad
TFP Expert
LifeTime Supporter
Apr 17, 2010
10,576
East Texas
I apologize for not being politically correct. He asked...I agreed with his offered surmise....and offered an alternative.
 

Green Goblin

Gold Supporter
Nov 5, 2012
92
Tennessee
In theory there should be some useful water in there. In practical application, I don't see how or why it would be helpful to you to do this.

First, that filter housing you are using is holding-- just a guess here, maybe 35-40 gallons of water in it. And it's got a bunch of stuff in it that you don't want in your pool. It would seem that to get useful water out of there you'd have to maintain the water chemistry properly in that barrel while it's in there, which may not be as easy as it seems given the bunch of nastiness in there and the temperature rise such a small amount of water may go through. Letting it settle for a day and trying to skim off the top, imagine you could get 20 gallons out of there that isn't too terrible looking-- even that seems like a high estimate... but if it was 20 gallons

And if you didn't mind the idea that you'd be putting some junk back into your pool that you just a day prior filtered out.. would all of this work be any easier than just turning your fill hose on for a few minutes while you are backwashing? What's 20 gallons of hose water cost you too? I think for me it's about 8 cents.

A typical garden hose on wide open does about 5 gals per minute, so if you set the hose running, then backwash, then turn off the fill hose, you might be close to breaking even on the whole deal.

It seems you'd be doing an awful lot of work for a few gallons of not so clean water.

Maybe you could trim your backwash hose to a shorter length so it's a little easier to do the backwashing?
 

Donldson

TFP Expert
LifeTime Supporter
In The Industry
Jun 12, 2009
3,943
NW Ohio
Ok, let me ask you a very simple question: Why?

Why do you want to put in so much work to reclaim a tiny bit of water? You don't live in an area where water is rare. You would inevitably reintroduce stuff that you don't want in your pool, possibly increasing your chlorine demand. And while you are leaving it sit I'm sure the mosquitoes will love laying their eggs in it. So what do you plan to accomplish?

If you are that worried about wasting water then switching to a large cartridge filter that only needs cleaned every couple of months would be a better solution.
 

cfclay

Well-known member
Apr 24, 2010
233
Lexington,Ky
It's really not a big deal , just discussion that's all. Unless I roll out 100 foot hose to discharge - Water collects in the neighbors yard during periods of heavy rain...and we've seemed to have plenty of that last summer and up through this month. Yard needs no water.

Discharge port is in extreme corner of yard
Ok, let me ask you a very simple question: Why?

Why do you want to put in so much work to reclaim a tiny bit of water? You don't live in an area where water is rare. You would inevitably reintroduce stuff that you don't want in your pool, possibly increasing your chlorine demand. And while you are leaving it sit I'm sure the mosquitoes will love laying their eggs in it. So what do you plan to accomplish?

If you are that worried about wasting water then switching to a large cartridge filter that only needs cleaned every couple of months would be a better solution.
 

Green Goblin

Gold Supporter
Nov 5, 2012
92
Tennessee
The issue really seems to be more about the backwash hose... as has been suggested a cartridge filter eliminates the backwash problem, but there's a non-trivial cost with that, and you're probably not saving yourself too much work. Either you're washing your cartridge or you're managing your backwash hose. I have done both of those things and really can't say why I prefer washing a cartridge to backwashing, I can't see that the effort is all that much different.

So with your backwash hose, could you just leave it out most of the time? I've done that before. It works great until you run over it with the lawnmower. Then you no longer get to say "100 foot backwash hose"

They do make reels for backwash hoses, maybe that would help.

You could have a couple of kids and make them backwash the pool every Sunday afternoon. That's how my dad solved this problem.
 

pookiesunshine

Gold Supporter
May 12, 2016
529
Cincinnati, OH
cfclay, i can see why you wouldn't want to unroll your long b/w hose every time and i will assume it is not practical to leave it out (as i do). i dont think that old filter housing would come close to holding my amount of b/w, but if it does yours and is easier, what about just letting it drain slowly into the yard after filling? you are still going to end up w/ junk in the old filter housing that will need to be cleaned out eventually. So maybe Green's suggestion of hose reel might be a better bet.