Have Scaling with First Opening

[joesc230]

Hi all,

My gunite pool was finished mid-August of last year. The pool was closed mid-October. Upon opening it this year, there was a lot of calcium that the pool's robot vacuum cleaned up. The water is looking good now, but the walls are quite rough. I'm assuming that this is scaling, right? (I've never had a pool before, so I'm learning as I go)

I did some searching online and it seems like a bunch of people run into this type of issue upon their first opening if they closed their pool not too long after finishing the plastering. I'm thinking that this is happening because the plaster didn't finish curing, but as a result of closing the pool nobody was brushing it and the pH was rising.

Since opening, I've been brushing the pool using a nylon brush for a few days now, and I do think that the scaling is slowly getting better. If I rub my hand along the walls, some of the crystals pop right off. Would I get better results if I switch to a nylon + stainless steel brush? Or a all stainless steel brush? Or, is my plaster still too new to do that? I don't want to cause further issues, and I'm willing to be patient and stick with the all nylon brush if that's the best way to go.

In case you're wondering how the chemistry of the pool is looking:

My initial readings, the morning after opening, were:
pH = way above 8.2
FC = less than 0.5
CYA = 25
CH = 200
TA = 60

The following day they were (after starting to shock and adding chemicals):
pH = 7.5
FC = 12.0
TC = 12.5
CYA = 30
CH = 200
TA = 80

Yesterday they were (after adding more chemicals):
pH = 7.4
FC = 9.5
TC = 10.0
CYA = 30
CH = 300
TA = 80

Today, it's the same, except the FC is 8.5 (and TC is 9).

Thanks in advance for any advice!

 

[Texas Splash]

It's great you have the TF-100. I wouldn't switch to steel bristles for a while until you know for sure that plaster can handle it. Lowering your pH was #1 - good work there. Interesting though that you show a 100 ppm increase in CH a day apart. Did you adjust to get into the recommended range perhaps? Now is the time where you use the row on the Poolmath Calculator titled "CSI" to ensure you keep that CSI at a neutral number (close to zero). In time it should help to reverse some of that scaling trend.

Curious about your FC. Are you trying to SLAM, or just keeping it a little high for now? A SLAM is common after opening, but would require an FC of 12 based on your CYA. But if you're just keeping it slightly higher for now after opening to see how things go that's fine. Just curious.

- - - Updated - - -

Oh, and remember, your TA serves as a buffer for pH. PH will rise quickly with new plaster, but the higher TA gets, the higher/quicker it allows pH to rise. If needed, it is okay to let the TA drop to about 60 if it will help slow-down the pH rise and help your CSI reading.

 

[joesc230]

Hi,

Ok, I'll stick with the nylon. Yes, I raised the FC to 12 (based on having a CYA of 30) to SLAM the pool after opening...it's been slowly dropping since then. Yes, the CH increase was due to me adjusting it to get in the recommended range.

Thanks for the other tips!

 

[joesc230]

Hi all,

I'm still working on brushing the scale off. Does anyone have any tips other than doing an acid wash?

For example, is there a certain product that should help? (but wouldn't cause other issues) Or, a certain chemical setting I should shoot for? I'd rather avoid acid washing only because the scaling does seem to be getting better (slowly), and because the pool is new and that would just really be a bummer to have to do so soon.

A question I have is, am I correct that getting the acid to around 7.3 or so (which is where I'm at now) is better as far as getting the scale off? If yes, should I be concerned that the CSI value isn't as good if I'm at 7.3 than at 7.5?

My current values are:

FC: 6.0 (still coming down from the SLAM)
CC: 0
CH: 300
TA: 80
pH: 7.3
CYA: 40

 

[Texas Splash]

After you enter all of your numbers into the Poolmath calculator, look at the row titled "CSI". As that number becomes more negative, but not below .6, it starts to become more acidic and may help to slowly over time reduce some scaling. It's a very slow process but might help.

 

[pooldv]

Agreed, keep your CSI at -0.3 to -0.4 and keep brushing. It is slow but it will not have any negative side effects.

 

[joesc230]

Thanks to both of you. I'll keep at it!

Is there a certain product out there that anyone would recommend to help speed along the scale removal process? (aside from doing a drain and acid wash)

 

[Texas Splash]

Many stores claim to have a scale removing or scale inhibitor product, but I'm not aware of any that actually do what we hope. I personally have tried a couple from the local pool store when I unknowingly (before TFP) allowed my pH and CH to rise too high together. None of those products worked. At $40 a pop, it can add-up quickly. I'm fine keeping my CSI at aa slightly negative number in hopes that the scale will eventually dissipate on its own through good chemistry. But if you find something out there and can crack the code on that stubborn stuff, let us all know.

 

[joesc230]

Many stores claim to have a scale removing or scale inhibitor product, but I'm not aware of any that actually do what we hope. I personally have tried a couple from the local pool store when I unknowingly (before TFP) allowed my pH and CH to rise too high together. None of those products worked. At $40 a pop, it can add-up quickly. I'm fine keeping my CSI at aa slightly negative number in hopes that the scale will eventually dissipate on its own through good chemistry. But if you find something out there and can crack the code on that stubborn stuff, let us all know.

Thanks for the info. I'm going to go with the CSI route and hope for the best.

 

[thelorib]

Is there a way to upload a picture so I can see if it looks like what Im dealing with? I cant get a pic to upload

 

[Texas Splash]

Have you tried linking your photos from Photobucket? That's what many of us do here on TFP. Upload your pics to Photobucket (free), then copy & paste the IMG code for that pic from Photobucket to your TFP post. Works great.

Also, you can try going to the bottom of your quick reply post where it says “Go Advanced”, and then down to where it says “Manage Attachments”. It may let you upload them that way. They may show-up large because you can't adjust the size of the attachment, but it may work.