FC below 3 ppm, for use with ScaleTec?

[nikolausp]

Hello, first time pool owner here. I touched on this in a different thread about a different issue, but I want to figure out a more detailed plan to deal with my Scale problem, and the Plaster Company's wishes.

My pool was filled at the start of 2021 (New Years Eve). The person that was hired to "Balance" my water didn't know what they were doing, and things like PH, TA, and everything else were MASSIVELY off the charts, all over the place, for 3 weeks (sometimes way too low, sometimes way too high). Finally he was fired by the Pool Builder, and I took over and had things balanced really fast, in a day or two, using TFP. Consequently , the pool developed a lot of scale during those first 3 weeks that won't come off with brushing.

The plaster company (not the plaster installers, but the actual plaster company, NFT POOL) want me to add ScaleTec to my pool, and see if it works, to get rid of the scale issues. In reading the ScaleTec instructions, it says it wants the FC to be lowered to 1.5 -2.0 FC, ideally, but certainly under 3. I called the ScaleTec company, and they told me that adding ScaleTec with FC over 3, is like adding water to the pool, since the ScaleTec will just get eaten up by the Chlorine, they said.

So obviously I don't want to do this during the Summer Time, due to CYA / FC chart and high sunny heat / UV levels, but I still want to make the Plaster Company (NPT Pool) happy, and my Pool Builder (who is clueless about water chemistry) says we have to do what the plaster company says (he's super stressed out.). So I'm kinda in a bit of a pickle. (and I'm also super upset about all this as well, the scale looks terrible).

That being said.... I was wondering if I waited to add ScaleTec in the Winter time when water is coldest as possible, would I have some lee-way with the FC levels & and potential algae growth? If I maintain my FC levels to say, between 2 and 3 in the winter time for say, 2 WEEKS, is there a chance that I won't get too much algae growth if the water is pretty cold (if so, how cold are we talking?). Is it best to not even consider doing this and just tell the Plaster Company NO?? Any thoughts, ideas / advice for how in the world I might successfully attempt to use ScaleTec with an FC level no higher than 3, I'm all ears.

In the meantime, after talking to ScaleTec company, I dumped in a bottle of their BeauTec , as they say Chlorine has zero effect on BeauTec. They said BeauTec might help with the Scale, but it will take much much longer than the ScaleTec. (Scaletec 2-4 weeks, BeauTec like 5-6 months or more.)

***as a side note, the person that failed for 3 weeks to "balance" my pool, was recommended to my pool builder directly by NFT POOL, since the pool builder said he wanted to "Cover His A**" with the water balancing. So that's another wrinkle. The plaster company is taking zero blame for how their recommended guy failed at water chemistry, so far.

 

[Texas Splash]

Well, you probably already know what our answer will be. I've not found any great benefits to using either of those products. In fact, I wonder how your plaster contractor would even know if you used it or not? But yes, in the winter our water gets chilly enough to avoid algae with a low FC level. Dec- Jan perhaps optimal. As for any scale from the previous chemistry experiments, you could use the PoolMath APP to keep the CSI level between -0.3 to -0.6 for a few weeks and monitor with consistent brushing. You might find better results that way. Keep in mind that even if those scale products did pull scale off the plaster, it's then in solution form so you really never got rid of it unless you change some water.

 

[nikolausp]

Thanks for the reply, and yes, I do know that it's totally not recommended..... Like I said, I'm in a bit of a pickle. Builder is stressed as heck, wants me to do what Plaster Company says, and me, well I want my plaster fixed and to look like a new pool! But I've also read the risks and negative stuff about the next steps they'll want me to take if ScaleTec doesn't work (no drain acid wash, then drain pool & acid wash, which will decrease my plaster's health and lifespan as I understand it), so if I try ScaleTec, I at least wanted to give it a chance to work in the best case scenario.

If it worked, I'd be fine with draining pool if that's the best solution, to get rid of the scale that would now be in liquid form, as you say.

I have been maintaining a CSI around between -.25 and -.5, for a couple weeks now, for the exact purpose you describe... should I just do that for a LONG time, and the problem will just go away eventually? I haven't seen any improvement, yet. How long is safe to go lower than -0.3 CSI?

In my searchings of TFP a month ago or so.... I found this INTERESTING post from 2015, about using ScaleTec, in Houston, in the middle of Summer, to great success. I reached out to this poster a couple times a few weeks ago, but never heard back. Any thoughts on what he did? He made PH super low, and got algae..... and then raised FC up a lot faster than what ScaleTec recommends. (they recommend keeping FC low for 1-2 weeks at least)

Should I use Scaletec or not?

First off, great site, and the iPhone App is cool Jason! (when is the Borate calc coming? ) 8-) So here's the story; our pool is going on three years old. 13' x 28' x ~4.5' infinite edge with a 3.5' x 26' x 2' overflow sump which equates to around 13k gallons total. SWG, Pebble-Tec, Sand...

www.troublefreepool.com

 

[Texas Splash]

I understand your tough spot. Maintaining the low CSI may help over time. There is no guarantee it will work exactly as you would hope, nor that the scale removal will be uniform across the pool. Just depends on how much the scale is embedded in various areas. An acid wash is certainly quicker, but as you said you lose a small amount of surface and longevity. But it's a process done frequently, and if your builder is willing to support it as a last resort under warranty, it may be the best route. In the meantime, you can continue the low CSI for a while to see if it helps.

 

[nikolausp]

I understand your tough spot. Maintaining the low CSI may help over time. There is no guarantee it will work exactly as you would hope, nor that the scale removal will be uniform across the pool. Just depends on how much the scale is embedded in various areas. An acid wash is certainly quicker, but as you said you lose a small amount of surface and longevity. But it's a process done frequently, and if your builder is willing to support it as a last resort under warranty, it may be the best route. In the meantime, you can continue the low CSI for a while to see if it helps.

Thanks for the insight. When you say "acid wash", which kind are you referring to? Drain, or No Drain?

In regards to my question about winter.... are you saying that I could lower my FC to say, 2.0 in Dec - Jan for say, 2-4 weeks or so, even with a CYA of 70, without having any issues? How cold would I need the water to get before attempting this? Would I likely need a SLAM afterwards? Or just continue as normal? Would I need to lower the CYA in that FC 2.0 scenario?

 

[Texas Splash]

I was referring primarily to a traditional acid wash - empty pool. No-drains come with their challenges as well though, so you have to be careful. As for winter, last Feb was an exception, but my water temp generally settles in the 50s from Dec - Jan. As we approach Oct, the angle of the sun and heat is much less, so you can let the CYA fall a bit. Once your water temps drops below 60, organic activity really slows down. Not that you can't still get algae, but it's much slower to develop. I think if you go into Nov with a crystal clear, algae-free pool, you can let the FC get lower as those water temps fall. Then you can do your scale treatment for a few days in Dec/Jan before increasing the FC again.

 

[nikolausp]

I was referring primarily to a traditional acid wash - empty pool. No-drains come with their challenges as well though, so you have to be careful. As for winter, last Feb was an exception, but my water temp generally settles in the 50s from Dec - Jan. As we approach Oct, the angle of the sun and heat is much less, so you can let the CYA fall a bit. Once your water temps drops below 60, organic activity really slows down. Not that you can't still get algae, but it's much slower to develop. I think if you go into Nov with a crystal clear, algae-free pool, you can let the FC get lower as those water temps fall. Then you can do your scale treatment for a few days in Dec/Jan before increasing the FC again.

Thanks for the water temp info, that's good to know.

The thing is, I'm not talking just a few days here.... The ScaleTec company recommends like 2 weeks. Thoughts on 2 weeks?

 

[Texas Splash]

The ScaleTec company recommends like 2 weeks. Thoughts on 2 weeks?

If it's something you are committing to doing, I'd say go for it. Watch the weather projections in that time frame and try to do it when you know we won't have some weird TX spike in temps. For us, Jan is typically the coldest, so you should be okay. You might ask about using Polyquat 60 algaecide in conjunction with the ScaleTec. That might be some good insurance during that period.

 

[nikolausp]

If it's something you are committing to doing, I'd say go for it. Watch the weather projections in that time frame and try to do it when you know we won't have some weird TX spike in temps. For us, Jan is typically the coldest, so you should be okay. You might ask about using Polyquat 60 algaecide in conjunction with the ScaleTec. That might be some good insurance during that period.

Ya, the actual ScaleTec instructions mentions using an algaecide, but I didn't really know what that is. Here's a screenshot. Do you know anything about Plolyquat 60? Is it just something I simply pour into the pool?

 

[nikolausp]

Assuming by some miracle , the ScaleTec treatment actually works, and the scale, as you say, would then still be in the pool in liquid form, would it make sense to then go ahead and drain the pool and refill it, to get rid of it completely, so to speak?

 

[Texas Splash]

Do you know anything about Plolyquat 60? Is it just something I simply pour into the pool?

Basically yes. Northerners use it every winter. Just follow the instructions on the bottle. It's a non-copper product which is good.

would then still be in the pool in liquid form, would it make sense to then go ahead and drain the pool and refill it, to get rid of it completely, so to speak?

It would, assuming your local water isn't too terribly hard. We can get a lot of rain that time of year too, so you might get lucky with some fresh (soft) water.

 

[nikolausp]

Basically yes. Northerners use it every winter. Just follow the instructions on the bottle. It's a non-copper product which is good.


It would, assuming your local water isn't too terribly hard. We can get a lot of rain that time of year too, so you might get lucky with some fresh (soft) water.

My fill water is around 50 to 60 CH, the few times I've tested it over the past several months.

 

[Texas Splash]

My fill water is around 50 to 60 CH, the few times I've tested it over the past several months.

That should work well.

 

[nikolausp]

How long is it safe to go low, between -.3 and -.6 CSI? (assuming that all my numbers are in acceptable TFP range?)

 

[Texas Splash]

How long is it safe to go low, between -.3 and -.6 CSI?

As long as the pH itself isn't extremely low (i.e. below 7.0) that by itself would be corrosive, your CSI can be in the range for a considerable amount of time. In your case, if you started now and don't begin to see any positive changes by the end of the year, I'd just try your experiment in Dec-Jan. If that doesn't work, prepare for an acid wash.