Please help. Hardness issue with brand new plaster

[Lori O]

We just got our 16 yr old pool replastered for the first time a few days ago. Leslies pool tested my new (chemical free) water and told me that I need 67lbs 8 oz of Hardness plus and also 1 quart of muratic acid in a 27,000 gal pool. They told me to put them in 4 hrs apart and told me that they were currently out of the product and sent me to anlother Leslies store. The girl at the second Leslies store told me that I would be crazy to put in more than 25 lbs because the plaster could start cracking. water test showed calcium hardness to be 50 and should be 200-400ppm, cyanuric acid showed 0 and is supposed to be 30-99ppm, total alkalinity shows 70 and should be 80-120ppm, ph is 8 and is supposed to be 7.2-7.8.

We put this pool in 16 yrs ago and always had great levels but never once used anything except for chlorine, muriatic acid once or twice and shock. I dont even know what hardener and conditioner are because I have never needed them or purchased them. Please advise me before I put the wrong chemicals in

[mas985]

Usually, the plaster installer will have a start up procedure to follow and it is normally tied to the warranty so it is important to find out if they have a recommendation. But a traditional start up keeps the PH at the lower end of the range (~7.2) brushing the walls and bottom every day until the plaster dust is gone. The filter will clog up quickly so it is important to clean it when the pressure rises significantly (50%). However, I would not add any CH to the pool at this stage because the plaster dust will dissolve and add plenty of CH to the pool and it is likely to be more than you want.

As for chlorine and CYA, what do you normally use to chlorinate the pool? If you are using BBB, then yes, you should add CYA (enough for 30 ppm) but not directly to the pool water as it can damage the plaster surface. It is better to add it via the skimmer or let it dissolve it in a sock in front of the pool return.

[Lori O]

Thank you for responding. The plaster company gave me a sheet of instructions but it only said start by balancing your PH. It did not talk about which chemicals and when to use them. I do not know what the BBB is that you are referring to. We have always used 3 in chlorine tabs in the floater and usually have to shock the pool once a month in the summer months. I am in Texas so there are a lot of Summer months. Since we put this pool in 16 years ago, I have only had to use chlorine, algaecide a few times and muriatic acid once or twice. The pool always looked great until this year when we had a lot of mustard algae growing and could not stop it with any traditional methods. The pool store told us that we locked up the chlorine and would have to empty 2/3 of the water. We decided that if we had to empty it we would just go ahead and replaster for the first time

[BigDave]

16 years ago when the pool was built, did the builder start it up, balance the water before turning it over to you?


You will need calcium to protect the new plaster. Calcium chloride is generally used to raise Calcium Hardness. It's available in the north in the winter as Ice Melt. I'm not sure if it's readily available in the summer in Texas. 50 lbs of calcium chloride (or 66 lbs of calcium chloride dihydrous) should get you to around 250ppm. Don't just dump it in, put some in - get it dissolved and mixed (run the pump) then repeat. Too big a dose in one area can cause a cloud in the pool. I wrote this paragraph before I saw mas985's post. I trust his opinion so please diregard unless your CH contines to measure low.

Buy an OTO / Phenol Red test kit locally.
Order a Taylor K-2006 or K-2006C if you don't already have one (no available locally).

Cyanuric acid is also called stabilizer, you'll need some in the water so the sun doesn't burn off all the chlorine. I like dichlor for starting new water - it dissolves quickly adds about 9 ppm CYA for every 10 ppm of Free Chlorine and reduces pH. The pool will need chlorine while starting up or you'll have to fight algae while trying to balance the water. Leslie's sells pure, unadulterated dichlor(99%) (last time I checked) called Chlor Brite in convienient one pound dose packs - it's expensive - If you have access to a Sam's club, they sell pure dichlor at a good price in a 24 pack of one pound packs or in a 50lb bucket. 15 lbs should get you to about 30ppm CYA (not all at once); you may want it higher in texas where it's hot and the sun is strong. 24 lbs will get the water to ~ 50ppm CYA which is a pretty safe level. To dose, dissolve a pound in a 5 gallon bucket (doesn't have to be full) of pool water then pour soulution around pool (pump is running). Start with two doses and add a dose every time the OTO test shows less than 3ppm chlorine. Test several time a day at the beginning because the sun will destroy the chlorine quickly until the CYA level comes up.

Keep an eye on the pH, if it's at either end of the scale on your tester, you'll need to adjust it. Use Borax to raise it if it's too low and Muriatic Acid to bring it down if it's too high. New plaster tends to cause pH rise and the dichlor may not bring it down enough. Please read and understand Using Muriatic Acid to Safely Lower Your Pool's pH int the Testing and Adjusting Pool Water Chemistry forum. While you're there, look at How to Get the Right Testkits for your Pool and order a K-2006 through the links (Pool Forum gets some cash to keep the lights on).

Did you order the K-2006 yet?

Baking soda (Arm and Hammer orange box) is best to raise TA - you don't need alot, 70 is OK no need to hurry this. DO NOT add baking soda at the same time as calcium chloride - this will also cloud the pool.

Read through the stickies in the chemistry and poolcare forums here and read the guides on poolsolutions.com, especially the Best Guess Chlorine Chart.

BBB is the method of poolcare we teach here. Read all you can, you'll learn there's no such thing as chlorine lock and that you can't really trust the poolstore. The method taught here is a safe, efficient and effective way to operate your pool. I hope you'll join me, mas985 and the thousands and thousands of other pool owners who've freed themselves from the poolstore.

Keep in touch, stay calm, it's eaisier than it seems.

[Lori O]

Thanks so much for your help. I will order the k2006 from your links if I can't find it locally.

[Watermom]

I'd be totally shocked if you found it locally. Do not buy the K-2005 by mistake. It is NOT what you want.

[Lori O]

Thanks for the heads up