High CH - 3 year old pool

[tjfontaine]

Hi gang.

I have a 3 year old pool - salt water 16000 gal with a SWG. I live in Metro Phoenix.

The first year my SWG worked great. 2nd year I was seeing a lot of white flakes in the pool and the SWG would clog frequently. It finally got so bad I took it out of the system and went to chlorine tablets. This has been true of at least 5 other friends in my area - most have given up on the SWG.

My current CH is over 700. I measured water out of the tap here (non softened) at over 350ppm CH.

I'd like to get this under control again for a whole number of reasons.

I could drain and refill but I will be behind the 8 ball to begin with. My autofiller is non-softened water. To make things more challenging I am a snowbird so not here in the summer (I use a pool guy). I turn off the water to the house but the pool autofiller bypasses that.

I am thinking of hiring one of those companies that comes out with a LARGE filtration system on a trailer. They will pump out filter and refill your pool with old water leaving the water chemistry "perfect" and a CH just over 200 (they also will put the salt back in to targeted ranges).

My questions - what is the thinking on this process?

2nd - how might I deal with the auto-fill which will then refill evaporated water with non treated 350ppm CH water? I thought perhaps I could install a large filter (RO?) inside my garage plumb the pool filler water into and out of that - if a filter could handle this.

Thoughts?

 

[domct203]

Hi gang.

I have a 3 year old pool - salt water 16000 gal with a SWG. I live in Metro Phoenix.

The first year my SWG worked great. 2nd year I was seeing a lot of white flakes in the pool and the SWG would clog frequently. It finally got so bad I took it out of the system and went to chlorine tablets. This has been true of at least 5 other friends in my area - most have given up on the SWG.

My current CH is over 700. I measured water out of the tap here (non softened) at over 350ppm CH.

I'd like to get this under control again for a whole number of reasons.

I could drain and refill but I will be behind the 8 ball to begin with. My autofiller is non-softened water. To make things more challenging I am a snowbird so not here in the summer (I use a pool guy). I turn off the water to the house but the pool autofiller bypasses that.

I am thinking of hiring one of those companies that comes out with a LARGE filtration system on a trailer. They will pump out filter and refill your pool with old water leaving the water chemistry "perfect" and a CH just over 200 (they also will put the salt back in to targeted ranges).

My questions - what is the thinking on this process?

2nd - how might I deal with the auto-fill which will then refill evaporated water with non treated 350ppm CH water? I thought perhaps I could install a large filter (RO?) inside my garage plumb the pool filler water into and out of that - if a filter could handle this.

Thoughts?

Hello, and welcome to the forum!

It sounds like your CSI was very positive, allowing scale to form and clog the plates of the SWG. There are a few members here with very hard water who successfully manage their pool with CH in excess of 700ppm.

How do you test your water?

What is your idea of 'perfect' water chemistry? After an RO treatment you will most likely need to balance the water. An RO treatment is not a silver bullet, and will not prevent the problems you are having unless you properly manage the water chemistry after the treatment.

Do you realize that those chlorine tablets are adding to your CYA level? Eventually your CYA will rise to levels that will make managing sanitation very difficult.

Do you know what your current CYA level is?

I do not know of a consumer grade RO system that is cost effective.

If you stay on top of your CSI scale should not be an issue, even with CH levels above 700ppm.

 

[tjfontaine]

Thanks for the response. I probably still have some learning to do. I used pool math my CSI calculates to .74 ..... my CYA level is 120 .... is there something I should be using instead of chlorine tablets until I can get my SWG going again without such buildup?

I treat weekly with 32 oz of Muratic acid try to get the pH down to 7.6 or so (a challenge) ... last check I did BEFORE treating it was at 7.8 and TA at 140.

Should I be trying to treat with acid more often to get that TA down closer to 80 and aerate if needed to then bring the pH up a bit? If I can get my csi to around .6 should I reinstall my salt cell and give it a try?

TIA

 

[mknauss]

Welcome to the forum!

Your best bet right now is to drain and refill to reduce your CH and CYA. You could also use a Reverse Osmosis service available in the Phoenix area. The RO process will be much more expensive than draining I would suspect.

This way you can start over and get control of your water chemistry from a fresh start. You will need a proper test kit (TF100 from TFTestkits.net or a K2006C). I suggest getting a SpeedStir with your order.

When you are refilling, you would get 30 ppm of CYA into the water and use muriatic acid to lower your TA over a few days time. Then you can control your CSI with pH, TA, and monitoring your CH. I manage my water to 1000 ppm CH and then drain/refill. I have never had scale on my SWCG. My fill water has 250ppm CH and 130ppm TA.

During the winter you can chlorinate with liquid chlorine until early March when you would raise your CYA to 70 ppm and start your SWCG.

Keep asking questions. Review Pool School, there are lots of information in there.

Take care.

 

[cfherrman]

Use bleach to clorinate your pool when not useing the swg, plain 8.25% bleach

 

[tjfontaine]

Tthanks guys - appreciate the help! I do have a K2006 test kit I use. The speedstir is a nice recommendation just ordered.

As to chlorine when not using my SWG - I am a snowbird and gone in the summer. I use a pool guy when I am gone. My pool guy uses Thrichlor?? tablets. Would I be best off to have the SWG out and have him use liquid chlorine? Can I use the stuff you buy at Home depot or just get Hilex or ?

I do think I will just empty the pool this year when it gets cold enough (I am in Phoenix and likely I will use it til mid dec). Then I will get the chem back in order and try re-installing the SWG (It is out of the system now). Mknauss and domct206 - appreciate the comments on high CH vs. just managing to CSI. I assuming it was the high CH (currently over 700) and no way around that.

TIA - again

 

[mknauss]

How long are you gone from your pool in the summer?
A pool service cannot use liquid chlorine as it has to be added DAILY.

We leave our pool for up to two months in the summer. We use a pool service and they come each week and check the pH, add acid as necessary, and clean the pool. They can adjust the SWCG but they are not able to (nor willing to learn) test the FC high enough to do any good. So before I leave I set the SWCG to create plenty of Chlorine based on our CYA.

However, because they only come by once a week, the TA in the pool increases over time. And thus the CSI increases as at the same time CH is increasing because of evaporation. So, when I return, many times my TA has climbed to above 100 ppm and the SWCG is sloughing flakes of calcium at polarity reversal. So then I need to drive down TA to 80 or less.

My question on how long you are gone is because if it is for the typical 'snowbird' time, eg mid-April to October, you will have difficulty managing this pool. In fact, the easiest may be to drain and refill each fall when you return, use your SWCG over the winter, then turn it off and let the pool service use Trichlor (tablets) over the summer, and then you drain in the fall, and repeat.

Hope this helps.

Take care.

 

[tjfontaine]

Thanks Marty??? I think this might be the best advice I have gotten. You described EXACTLY my situation - gone for 5 months. I think I should just drain and refill each year it is not that much money even here in AZ. That helped - a lot.