Course of action for hard water? Reverse osmosis? Water Softener? Both?

johig

Gold Supporter
May 23, 2019
64
Mission Viejo, Orange County, CA
Pool Size
17000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
My calcium hardness has gotten very high (~1,200) due to my local hard water supply and three summers of evaporation. I don't want to drain and refill due to the current severe drought. Unless I want to deal with high calcium forever, I think I need to get a water softener for my autofill line. Is there a realistic chance this will bring down calcium levels noticeably over time, or should I plan to have the pool treated with reverse osmosis and start over with low calcium hardness and then use softened water? If anyone has a referral for a good RO company in Southern California, please share.

For the water softener, I have a couple of installation options. I can do a traditional installation so that it serves my whole house (except exterior irrigation). I think I also have the option to install a dedicated softener at my pool equipment pad because my autofill line routes through there and there is electrical power as well as a drain to the sewer (for backwashing). Has anyone tried adding a water softener at their equipment pad? Were there any notable pros or cons? I definitely want an automated system and not something that requires manual backwashing.

Are there any other options or solutions I should be considering for dealing with hard water long-term? I read a bit on the forums about using an RO unit on the autofill line but it sounded like that might waste more water than a softener.

Thanks in advance for any advice!
 
It's not going to decrease any appreciable amount even with significant amounts of splash out or overflow from small amounts of rain you'll get. Imagine splashing out half of your pool to cut the calcium in half. It isn't practical.

Adding a softener is a great step. But you'll still need to drain 75% of the pool or do a RO treatment to get the calcium way down.
 
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I did RO and then got a portable RV water softener and it has worked well for me so far.

Here’s my RO post so you can take a look.
Post in thread 'Reverse Osmosis'
Reverse Osmosis

And some more. This one also has discussion about water softener
Post in thread 'Ph after water softener First readings'
Ph after water softener First readings

Here’s the softener I purchased. I just hook it to my hose bib:
On The Go OTG4-VM-DBLSOFT... https://www.amazon.com/dp/B085Q2LBJV?ref=ppx_pop_mob_ap_share
 
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Have you tested your house water to know what you’re adding when you top up the pool? I wouldn’t imagine it is more than CH 250 ppm. Have you added any calcium products, like cal-hypo to raise FC?

I/we lived in RSM till the end of 2019. When we lived there, we were on a 5 year cycle to drain and refill. But that was before I found TFP. Then we moved here to Las Vegas a year after discovering this forum.
 
I went the route of installing a whole-house softener with a plumbing run out to my auto fill line (it was a good location that was close to the softener loop in the garage). A whole-house solution is better since your home appliances and fixtures are getting ruined by high hardness water anyway. The next best solution would be doing it outside at the equipment pad BUT you need to find a softener that’s rated for outdoor use (meaning it can withstand rain, heat, cold, etc). Those types of softeners are harder to find. Get the largest capacity water softener you can find.

I was at 1500ppm CH in my pool when I made the switch. I had to do two very hard drains to get the CH down to 550ppm. In two years after doing that my CH only went up by 25ppm to 575ppm. 25ppm increase in two years. That’s fine by me. And, my family and water heaters appreciated the softened water.

You’ll have to do RO to get your CH down but do realize that RO is only about 80-85% efficient so you will be using a good amount of make-up water to replace the waste water generated by the RO process.
 
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Have you tested your house water to know what you’re adding when you top up the pool? I wouldn’t imagine it is more than CH 250 ppm. Have you added any calcium products, like cal-hypo to raise FC?

I/we lived in RSM till the end of 2019. When we lived there, we were on a 5 year cycle to drain and refill. But that was before I found TFP. Then we moved here to Las Vegas a year after discovering this forum.
The house water is right around 250 ppm CH. After the initial fill, I deliberately added calcium to bring the pool up to 350. (In hindsight, I needn't have bothered.) Since then, there have been no calcium products added. I think it's just an evaporation problem which I attribute to our dark StoneScapes finish, full sun, and a lot that is not very sheltered, so there is often a pretty good breeze.
 
I did RO and then got a portable RV water softener and it has worked well for me so far.

Here’s my RO post so you can take a look.
Post in thread 'Reverse Osmosis'
Reverse Osmosis

And some more. This one also has discussion about water softener
Post in thread 'Ph after water softener First readings'
Ph after water softener First readings

Here’s the softener I purchased. I just hook it to my hose bib:
On The Go OTG4-VM-DBLSOFT... https://www.amazon.com/dp/B085Q2LBJV?ref=ppx_pop_mob_ap_share
Thanks for the input and the links. The On-the-Go softener looks great and is pretty reasonably priced. I'm leaning toward a whole-house softener but it's great to have an affordable recommendation in case I decide to just treat the autofill line.
 
I went the route of installing a whole-house softener with a plumbing run out to my auto fill line (it was a good location that was close to the softener loop in the garage). A whole-house solution is better since your home appliances and fixtures are getting ruined by high hardness water anyway. The next best solution would be doing it outside at the equipment pad BUT you need to find a softener that’s rated for outdoor use (meaning it can withstand rain, heat, cold, etc). Those types of softeners are harder to find. Get the largest capacity water softener you can find.

I was at 1500ppm CH in my pool when I made the switch. I had to do two very hard drains to get the CH down to 550ppm. In two years after doing that my CH only went up by 25ppm to 575ppm. 25ppm increase in two years. That’s fine by me. And, my family and water heaters appreciated the softened water.

You’ll have to do RO to get your CH down but do realize that RO is only about 80-85% efficient so you will be using a good amount of make-up water to replace the waste water generated by the RO process.
Thanks for the input. I was aware of the loss during RO, but that's definitely important to know to avoid future disappointment. One of the RO vendors I spoke to did a pretty thorough job explaining the process. She also confirmed that they pull the makeup water from my home supply and treat that as necessary on its way to the pool. So they handle the top-up and make sure that the finished pool water has appropriate chemical levels.
 
But do they have a TFP mindset for pool water chemistry? It's your pool make sure they don't add anything that is not recommended.
That's a very good point. I'll make sure we agree on target levels in advance and that I test them for myself before they leave.
 

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When I did RO I told them what I was going for and they were receptive and followed. Their levels were actually in line with TFP, except they did put a little more chlorine. I think you’ll be fine going this route. I tested before RO, half way point, at the end of RO, and at the end of them adding the chemicals. I also retested a few days later. It really helped me get a handle on testing and knowing where everything stood.
 
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