Should I Drain My Pool?

DanF

Silver Supporter
Mar 17, 2019
594
Chandler, AZ
Pool Size
12500
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
CircuPool RJ-45 Plus
I'm trying to decide whether to drain my pool, now that the weather is cool enough to do so. Goal is avoid scaling of salt cell and pool waterline.

Here are my readings, taken today:
FC 8.0
CC 0.0
pH 7.6
TA 80
CH 850
CYA 80
Temp 54
CSI -.13

Yes, I could probably knock the CSI down a bit with lower pH and TA but with the lower temps right now I'm not that concerned. My dilemma is that when the weather warms up the CH will rise and the higher water temps will cause the CSI to rise as well. In summers past I've been as diligent as possible in trying to keep TA low by aerating and adding acid. This tends to keep CSI between -.2 and -.3.

I know that I really should have a softener on my auto-fill, but my auto-fill is plumbed off of my irrigation system, so connecting to my water home softener to it is not an option without some serious work. I have the auto-fill connected to my irrigation system because when we leave in the summer for a month or more I turn off the main water supply to the house. Only real option for me in this space is to install an RV softener and I'm not sure I want to mess with the manual regens but I would if it were worth it.

My fill water is typical for folks in the AZ deserts: 7.7pH/130TA/190CH. I drained the pool two years ago, but the CH seemed to creep up fast. Does it help to rinse the pool while draining (and before refiling)? Water costs are reasonable here as opposed to an RO exchange, so I would likely go that route.
 
Consider waiting until spring - maybe late February or early March.
It's easy to manage your present CH and TA with our present lower water temps.

In a year, your CH will rise 250 or more (mostly do to high evaporation in the late spring thru early fall) because of the hardness of our water.

You're in Chandler, as am I. We pay a flat sewer rate. The city does NOT base the sewer rate on spring time water usage like Mesa does (although Mesa will allow a pool refill exemption). It doesn't matter, based on water cost pe4 gallon, when you drain/refill.

I rinse my walls while draining. No idea if that helps, but in my mind I think it does.

Seriously consider adding a water softener. Either a whole house or just a dedidated one for your pool.
You refill the pool with plain tap water and use softened water for the autofill. Your CH will remain relatively constant for a long time. After I plumbed my softener to my autofill, my CH has risen less than 100 ppm in 3 years - and that was probably from the softener regenerating during the time the pool autofill was running.

When you refill and add salt, try to stay on the low end of the range Circupool recommends. Working the TA of 130 down to 60-70 and the added TA from make up water do to evaporation will require adding muriatic cid, which adds some salt as well.

Keep the CSI in the 0.00 to -0.30 (negative 0.30) range to minimize SWG scaling. You will need to monitor pH, TA and water temperarure to keep CSI within that range. The pH will be the most important parameter to keep in check to manage CSI. My SWG is about 2 years old and has never had any scale. There are other members here that have harder water than you and I, and they don't get scale in their SWG because they manage their water chemistry to keep CSI in check.
 
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It took about five years for my CH to rise to 550. I did a small exchange (about 18") and that got it back to about 350. I have my auto-filler connected to my softener. Before that, CH destroyed my plaster (the previous owner ignored the CH and I bought the house and pool with the plaster already ruined). So the work involved in running the line from softener to auto-fill was worth the trouble.

Going forward, I'm going to exchange once a year, so that I can exchange less. I'll keep my CH between 350-450. I never want to drain my pool. I feel it is too risky. I would advise anyone the same. You could probably get away with it. Sounds like you have. And you might again. But the water is part of a pool's structure, and removing all that counter-force suddenly, IMO, is just asking for trouble. So I'll do a little at a time, and minimize the risk.

Alternately, you can do a no-drain exchange. It uses more water, but you never let the level drop at all. I'll likely do that next time.

Regarding your dilemma about leaving for a month, this is how I handled that. My auto-filler was also plumbed to my irrigation system. When I connected the softener, I left the original connection in place. I added a valve to it. And then tee-inned the soft water pipe, also with it's own valve. That way, I can send soft water or street water to my auto-filler. Turn them both off. Or mix the two if I want to. Like you, I assume, my softener is on the house-side of my house's water shut-off valve, which I like to close when I travel. In that case, I would shut off the soft water to the auto-filler, and then turn on the hard-water supply to it. Then shut off my house.

I included a proper backflow preventer to the auto-fill. And I also added two cheapie check valves to both the soft water feed and the hard water feed. That way, should the two valves inadvertently be left open, water won't cross over between my irrigation system and my house system. It's possible, because the house is on one side of my main pressure regulator, and my original auto-fill feed is on the other. So if both valves were open, without those check valves, I think water would cross between the systems (like if I turned on a sink faucet, hard water would force its way backward and into into my house).

Anywho, pull the triggers:
- do a partial exchange to bring your CH down, consider a no-drain exchange
- do them more regularly so that you can exchange less at a time
- connect your auto-filler to your softener, and leave the original connection in place, with two valves to allow you to choose between fill sources.

Here's how I did it. This is a huge thread I started when I first came on board here. About all my trials and tribulations, including dealing with CH and high TA. The bit about the softener hookup starts at post #76.

Here's the no-drain exchange instructions, about halfway down this article:
 
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Additional tips:

- I wrangle rain in the winter, as much as possible, to create mini exchanges. That's free, zero-CH water!

- I filled that 18" exchange with my softener! I did an extensive study about it, and monitored the CH as I filled. I actually got almost the entire exchange done, but had to regenerate towards the end. That's the other reason I'll exchange more often, so that I can complete the fill on one regen cycle. I kept a spreadsheet of the whole effort, to calculate how much I can exchange and then refill from my softener. By filling with soft water from the softener, instead of my high-CH street water, I can exchange considerably less.
 
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As @Dirk said, it is worth the effort to plumb the softener to the autofill. It might take a bit more work, but you only have to do it once instead of draining/refilling every 2-3 years. One and done.

Doing a full drain/refill in cooler weather shouldn't be an issue here in the desert southwest. Dry weather and a very low water table help make it a safer option. Of course, you need to be comfortable with doing so and assume any liability. Personally, I've done mine probably 6-8 times over the last 24 years without issue. Fast drain and quick refill - toss as many hoses in as you have hose bibs. Pool in completely empty for a minimal time - only a few hours.

Your call how you do it, but a major water replacement to lower your CH is needed before summer.
 
More tips:

- If you had a softener (and plumbed it the way I did) and wanted to leave for a month, you could raise the level of the pool water as much as is safe with soft water, then switch over to your hard water source. That way, it would take a little longer for the pool to evaporate before the auto-filler called for that nasty hard water.

- Like Gene (above), I suspected my pool was filling some amount while my softener was regenerating. That would send hard water to the pool (as a softener shuts down, bypasses itself, while regenerating, but continues to supply street water to the house during the cycle). So... I added an automated valve to my auto-fill system. Each night my pool automation system closes that valve. I bracketed the schedule around when my softener regenerates. So if my auto-filler calls for water at 4:00am while my softener is regenerating, no water can get to the auto-filler. When the softener finishes its cycle, and my automation opens the valve again, the pool will refill at that point, using "freshly squeezed" soft water! I think I wrote that up, too, somewhere, but if you want the deets, I can give you the parts list. It was a simple mod.
 
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Fast drain and quick refill - toss as many hoses in as you have hose bibs.
The only issue with that MO, is that you're refilling with high-CH water, so you're losing ground from the get go, and having to exchange way more water. My MO, refilling with soft water, allows for a much smaller exchange. I've only done it once so far, but it worked great. I'd refill an inch, and then test my fill water for CH. Each time getting pretty much CH zero. I kept doing that, one inch at a time, until I saw a little CH in the test result. Then I stopped the fill, regenerated for a couple hours (by then the pool was almost full, so it was pretty much risk free), and then commenced the fill. I only had to regenerate once. And next time, since I'll be exchanging way less, I'll get the refill done without regenerating at all (except once before I start the process).
 
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200-ish fill water - so CH would be less than 250 ppm with a full drain/refill.

Several ways to get this done and achieve roughly the same result. OP has some options to consider and planning to do.
 
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200-ish fill water - so CH would be less than 250 ppm with a full drain/refill.

Several ways to get this done and achieve roughly the same result. OP has some options to consider and planning to do.
Absolutely.

My fill water is closer to CH350, so I have to be a little more drastic.

Sure, if he's going to exchange the whole pool, or most of it, he'd want to fill from the street. He'll end up with CH pretty much where it should be. You'd never want to fill an entire pool with soft water, even if you could.

No, I was referring to maintenance exchanges going forward, after he gets his CH back to normal. If he exchanges more often, not letting it go three or four years like I just did, then he can do a much smaller exchange, maybe 6 to 12 inches, if he fills with soft water. Anyway, that's what I'm going to try for a while to see how it works.
 
toss as many hoses in as you have hose bibs
In case you didn't catch this (I mention this in my thread about hooking up my softener). When I ran a pipe from an existing soft water line to my autofill, I ran it down from the attic through an exterior wall, then outside through the wall, then down into the dirt to find the line that feeds my auto-fill. I added a hose bib on the wall, thinking I could use soft water to wash my car or my PV solar panels. I use that bib for filling the pool, too. It's not as fast as multiple hoses, but it's faster than the auto-fill.

So if you go this route, plan to include an exterior soft water hose bib. Comes in handy.
 
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Seriously consider adding a water softener. Either a whole house or just a dedicated one for your pool.
Agree...I've been thinking about it for sure. We have a whole-house one now, which is plumbed into the soft water loop that was installed when the house was built. The softener itself is fairly new. However, the loop doesn't include any of the exterior hose bibs, nor the cold side of the kitchen sink.

So I would need to either extend my in-house system to the auto-fill somehow, or go with one of those portable RV-type systems. If I knew I was going to be in the house for awhile I might look into the first option.
Regarding your dilemma about leaving for a month, this is how I handled that. My auto-filler was also plumbed to my irrigation system. When I connected the softener, I left the original connection in place. I added a valve to it. And then tee-inned the soft water pipe, also with it's own valve. That way, I can send soft water or street water to my auto-filler. Turn them both off. Or mix the two if I want to. Like you, I assume, my softener is on the house-side of my house's water shut-off valve, which I like to close when I travel. In that case, I would shut off the soft water to the auto-filler, and then turn on the hard-water supply to it. Then shut off my house.
That's a great idea. I am going to read your thread that you linked to above for more ideas and motivation. For now I think I may do a full drain soon, as there is some rain in the forecast toward the end of next week. I'm planning to be in the "fill" stage of the drain-and-fill when that happens :).

Thanks to both @proavia and @Dirk for your inputs.
 
It sometimes takes a little creativity to rearrange your plumbing. Remember, every faucet in your house, every shower and tub, the dishwasher and washing machine, are all soft water "sources." You don't need to limit the tap to the crawl spaces, or the softener itself. Identify the interior fixture, located on an exterior wall, that is closest to where you can tap into your autofill line, and use that!

Say it's a bathroom sink, or toilet. You open up a small square of sheetrock that includes the stop (the fixture's shutoff valve), spread aside the insulation, drill a small "locater" hole from the inside out to punch through the exterior wall, then drill the larger hole from the outside in. Then run your soft water outdoor spigot and supply line right from there. Restore the insulation and sheetrock, patch-patch, paint-paint, and you're done. If you tap from under a sink, you don't even have to be particularly skilled at sheet rock and painting, no one will ever see your work!

My thread will give you some ideas about how to build the outdoor components and connections. If you need any of it deciphered, or detailed, just holler.

This job might be simpler than you imagine.

Sidebar: if your plumbing aligns with the stars (and a suitable outdoor location), you could tap both the hot and cold pipes to outside, and plumb yourself a comfy outdoor shower! Just below the shower spigots will be your soft water hose bib, and then from there go on to your auto-fill. So the project could conceivably yield more than one great convenience/improvement.

The next homeowner won't appreciate the soft water for the pool, not until after they move in. So it won't help your sale. But an outdoor shower might. It won't fetch you more money, but it's the kind of nicety that can leave an impression. So even if you move sooner than later, it won't be entirely wasted effort.
 
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Great ideas, thanks Dirk. My issue is that my only exterior wall fixture is a 65' run to my auto-fill, with 50' feet of that under a concrete patio. Major excavation.

A potential alternative is tee-ing off of the water heater's cold inlet and run that up through the attic and over to the auto-fill area, then down the wall and out. Maybe.
 
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For now I think I may do a full drain soon, as there is some rain in the forecast toward the end of next week. I'm planning to be in the "fill" stage of the drain-and-fill when that happens
We may be lucky to get 1/2" total between Wednesday and Christmas Eve. Not enough to make any appreciavle difference.

Is any of your interior cold water plumbing (except the cold water for the kitchen sink) in an exterior wall close to the pool or autofill line?

I tapped into the cold soft water line in the garage, ran it thru an exterior wall, down into the ground (all copper) and transitioned to PVC once underground then along the side of the house to the autofill line. Neighbor tapped into his cold soft water line in the garage, ran PEX up and thru the attic, then transitioned to PVC when the line exited thru the soffit and down into the ground near the autofill line. There are many creative ways to do this.
 
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Yah, that sounds like a challenge. There is tech that can get a pipe under a slab, but I don't know what it costs. Probably not less than the cost of a 2nd dedicated softener just for your pool (~$500). I've seen that done here. Guy built a small shed for it, outside in his yard.

I just spent last week in my attic running cable, so I'm not shy about that. But my attic is tall and blown in (no fiberglass), to it's not awful working conditions.

Running PEX is pretty easy, depending on conditions in your attic.
 
It took about five years for my CH to rise to 550. I did a small exchange (about 18") and that got it back to about 350. I have my auto-filler connected to my softener. Before that, CH destroyed my plaster (the previous owner ignored the CH and I bought the house and pool with the plaster already ruined). So the work involved in running the line from softener to auto-fill was worth the trouble.

Going forward, I'm going to exchange once a year, so that I can exchange less. I'll keep my CH between 350-450. I never want to drain my pool. I feel it is too risky. I would advise anyone the same. You could probably get away with it. Sounds like you have. And you might again. But the water is part of a pool's structure, and removing all that counter-force suddenly, IMO, is just asking for trouble. So I'll do a little at a time, and minimize the risk.

Alternately, you can do a no-drain exchange. It uses more water, but you never let the level drop at all. I'll likely do that next time.

Regarding your dilemma about leaving for a month, this is how I handled that. My auto-filler was also plumbed to my irrigation system. When I connected the softener, I left the original connection in place. I added a valve to it. And then tee-inned the soft water pipe, also with it's own valve. That way, I can send soft water or street water to my auto-filler. Turn them both off. Or mix the two if I want to. Like you, I assume, my softener is on the house-side of my house's water shut-off valve, which I like to close when I travel. In that case, I would shut off the soft water to the auto-filler, and then turn on the hard-water supply to it. Then shut off my house.

I included a proper backflow preventer to the auto-fill. And I also added two cheapie check valves to both the soft water feed and the hard water feed. That way, should the two valves inadvertently be left open, water won't cross over between my irrigation system and my house system. It's possible, because the house is on one side of my main pressure regulator, and my original auto-fill feed is on the other. So if both valves were open, without those check valves, I think water would cross between the systems (like if I turned on a sink faucet, hard water would force its way backward and into into my house).

Anywho, pull the triggers:
- do a partial exchange to bring your CH down, consider a no-drain exchange
- do them more regularly so that you can exchange less at a time
- connect your auto-filler to your softener, and leave the original connection in place, with two valves to allow you to choose between fill sources.

Here's how I did it. This is a huge thread I started when I first came on board here. About all my trials and tribulations, including dealing with CH and high TA. The bit about the softener hookup starts at post #76.

Here's the no-drain exchange instructions, about halfway down this article:
what water softener do you use?
 
I just grabbed one from my local Lowes. I had sooooo much to do when I first moved in that I couldn't take the time to research it. But it's worked well. The buttons give me some grief (hard to press), but other than that, it's, you know, making soft water!


Lowes doesn't sell them any more (or mine doesn't). And, of course, they're quite a bit more expense now. Whirlpool still makes that model, but it's in a redesigned, narrower shape. I got the Whirlpool whole house water filter, too, at the same time, almost nine years ago.

@JoyfulNoise has good insights about water softeners.
 
I just grabbed one from my local Lowes. I had sooooo much to do when I first moved in that I couldn't take the time to research it. But it's worked well. The buttons give me some grief (hard to press), but other than that, it's, you know, making soft water!


Lowes doesn't sell them any more (or mine doesn't). And, of course, they're quite a bit more expense now. Whirlpool still makes that model, but it's in a redesigned, narrower shape. I got the Whirlpool whole house water filter, too, at the same time, almost nine years ago.

@JoyfulNoise has good insights about water softeners.
I actually I bought same brand but smaller model. Today is the first day using it. I am pumping the pool water through it.
 
I actually I bought same brand but smaller model. Today is the first day using it. I am pumping the pool water through it.
What is your pool water FC level?
Chlorine can ruin the softener resin.

What capacity is the water softener?
It should be listed in grains - 30,000 grains, 60,000 grains, etc.

Only tap water should be run thru the water softener.
 
What is your pool water FC level?
Chlorine can ruin the softener resin.

What capacity is the water softener?
It should be listed in grains - 30,000 grains, 60,000 grains, etc.

Only tap water should be run thru the water softener.
Yes, good call. I wasn't around to catch that earlier.

Let's hope he means he's running his auto-fill source through it...
 

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