No one wants to acid wash my pool

[Dom]

Hey all,
The last time I acid washed my pool was in 2009, The scale was really bad around the tile line and a lot had buildup between the pebbles. I remember the guy was concerned about acid washing my pebbletec he had asked me if I had ever done before, which I never did. He agreed to do it and when he was done it looked brand new. Ever since the tile line has remained scale free but it has built up on the floor, steps and spa between the pebbles, some areas have thicker patches of scale here and there. I recently had three different pool specialist come and look at my pool to consider acid washing , all three of them declined to do the job in fear of losing patches of pebbles. One of them recommended pouring acid directly into the spa he said to start with 2 gallons and said it may require a third, he said that over the course of the next 2 to 3 days to go out and scrub every 3 to 4 hours on occasion, he said it may not even require scrubbing sometimes! He said if it works on your spa it should work on the pool and that the pool would require 15 gallons of acid, and that is what he has done before and I should be able to do it myself.
Anyone have experience using this method on pebbletec?

 

[pooldv]

That is called a no drain acid bath. It is much less aggressive than a drain and acid wash, which can take years off the life of you plaster/pebble.

It is not difficult to manage your water chemistry to prevent scale in the first place and/or stop it from scaling further. It is also possible to manage your water with aggressive water for several months or a year to try to slowly dissolve the scale over time.

More here, Pool School - Calcium Scaling

 

[Dom]

Thanks for the reply pooldv! So is it safe to leave the acid in the pool and spa for 3 days with repeated scrubbing? Is the aggressive water you are referring to safe to swim in?

 

[Dom]

One other problem that just sprung up is or was a bad algae bloom. My wife had a some friends and kids over and had the spa running and heated. She turned off spa mode but not the heater, and proceeded to heat the pool for 3 days right as we were getting a heat wave on top of it all. I never saw the pool like this, I immediately got to chlorinating brushing, vacuuming and ran the pump 24/7, it cleared up by the next day but since the algae wants to come back. I noticed the chlorine is being consumed quickly. Which brings me back to the original reason for this post, I wanted to drain the pool to clean the scale but now I have the algae. Which do I address first? Here are chemistry readings.

 

[Rossterman]

cYA is way too high at 136 ppm! If you look at the cya/chlorine chart, it would indicates you will need to maintain 14ppm free chlorine and 50ppm to effectivley shock. That is ASSUMING CYA isnt actually higher. Do you have a taylor k2006 or TFP test kit? If not buy one and verify the readings before determining a course of action. When CYA is higher than 100 ppm you need to perform dilution tests to actually determine actual level. My pool store indicated my CYA was 112 when I did the proper testing doing dilution method, it was actially 320! I was maintaining what I thought were very high chlorine number (~10) and experiencing the same agle blooms you are having. The CYA is preventing the chlorine from effectively treating the alge unless you maintain it and shock it as above.

The good news is draining the pool will allow you to correct the high CYA numbers. As to whether pebble tec is near end of life and would be damaged irreparably by a wash, Id guess if two or three are saying the same thing, thoere is likely some truth in this. There is an acidwash additive that reduces the corrosivness of the acid (blaster white & bright) but even that may be too much. I just acid washed our 10 year old pebble tec and it looks better than new! With CYA at 45 now after the refill, 4ppm free chlorine keeps pool water sparkling now!

 

[pooldv]

Thanks for the reply pooldv! So is it safe to leave the acid in the pool and spa for 3 days with repeated scrubbing? Is the aggressive water you are referring to safe to swim in?

Yes, the aggressive water with CSI at -0.8 or so is safe to swim in. It is also the least aggressive, and least damaging, way to try to remove scale. And it will definitely prevent any scale from forming going forward.

The longer you leave the acid bath the more plaster layer it will remove. Most folks do an acid bath for 24 hours. But, I don't know how bad your scale is.

You do need to drain to lower CYA to 60 or so. Order are TF-100xl from TFTestkits.net and SLAM Process the pool to kill the algae.

 

[Dom]

Yes, the aggressive water with CSI at -0.8 or so is safe to swim in. It is also the least aggressive, and least damaging, way to try to remove scale. And it will definitely prevent any scale from forming going forward.

The longer you leave the acid bath the more plaster layer it will remove. Most folks do an acid bath for 24 hours. But, I don't know how bad your scale is.

You do need to drain to lower CYA to 60 or so. Order are TF-100xl from TFTestkits.net and SLAM Process the pool to kill the algae.

The scale is definitely not as bad as it was in 2009, the walls, tile line are scale free but the steps, spa steps and benches, and floor have some build up and thicker patches here and there. The local pool place says that CH out of the tap here is 400-500, and I have to add water often due to evaporation, I live in So. Cal we have not had much rain in a long time. But again the last drain I did was 2009! So I will do the no drain acid wash for no more than 24 hrs. and then drain and refill and then SLAM! Would that acid bath kill off the algae also? How much soda ash will I need when done with acid wash?

 

[pooldv]

I don't know. I would try to use Poolmath, Effects of Adding Chems, to calculate how much the acid will drop the PH and then calculate how much soda ash to raise it. Use less and test a couple of times. Afterwards use Poolmath to calculate CSI and keep it between -0.3 and 0 to prevent scale in the future.

 

[Dom]

Hello, finally got the no drain acid bath done and I am draining as I am typing. i definitely had an algae problem before i did some repairs to the spa and did the acid bath. I just need some advice on getting chlorine and CYA immediately in the water. Should i start dissolving some CYA as it is filling? I dont know how long it will take to fill. And should i start chlorinating as it is filling also? Need to get to SLAMming! Got my TFP test kit last week!

 

[pooldv]

Nice! It is fine to start the CYA dissolving now. No need to chlorinate until it is is full and the pump is running. Tap water has a little chlorine in it to hold you over.

 

[YippeeSkippy]

Your drain will also help remove the copper and iron your pool had in it. Yay! Do you know how your pool got those in there? Don't use any copper containing algaecides, metals in the pool cause stains.

Do you have one of the test kits we recommend?

 

[ping]

Add enough CYA to raise it to 20 for now. The pool will be easier to SLAM if the CYA is 20-30.

 

[Dom]

YippeeSkippy- I have the TFP test kit. Did i have to much copper and iron in my water. Should i have 0?

 

[max2k]

YippeeSkippy- I have the TFP test kit. Did i have to much copper and iron in my water. Should i have 0?

put test kit name in your sig or every other poster will ask the same question You should have 0 metals in your water ideally but fill water in some places has them already present. Hopefully not your case.

 

[YippeeSkippy]

Yes, your test results showed 0.2.. getting close to a problem there, and yeah you should ideally have none. Do you fill from a well or use algaecides? Some contain copper for example.

 

[Dom]

ping - According to Poolmath i need 75 oz. of CYA granules to get to 20. When I am done with SLAM should i bump it to 30? Im gonna fill an old sock with the CYA and hose clamp the hose in the sock as the pool fills. I am open to suggestions. I appreciate all of your guys feedback!

- - - Updated - - -

YippeeSkippy- I believe my previous pool guy did put some algaecide in my pool once or maybe twice. i remember it turned my pool brown for a day or so. i dont think my tap water comes from well water??

- - - Updated - - -

I tried editing my signature and had difficulty. I will try again when i get some time.

put test kit name in your sig or every other poster will ask the same question You should have 0 metals in your water ideally but fill water in some places has them already present. Hopefully not your case.

 

[pooldv]

Click Quick Links above and Edit Sig.

 

[Dom]

Thanks Pooldv! Do i have to run the pump 24/7 during the SLAM?

 

[pooldv]

Yes, best to run the pump 24x7 for max chlorine circulation to avoid dead spots for algae. On low is fine if it is 2 speed.

 

[Dom]

I need one of those 2speeds or VS's, but that is a whole other topic. Thanks!