Battling high alkalinity in new pool

Hello!

I've been reading these forums for quite some time now and I'd like to say they have been extremely helpful! I am a new pool owner; my fiancé and I bought a new home and acquired a pool and now *BAM* I need to become a chemist.

A little background and what the situation was a few weeks ago:
We live in Minnesota - the previous owners got foreclosed on and the old owner gave up on the pool last fall when the auto-cover went kaput. As you might imagine, the pool was an absolute swamp when we bought the house this spring and moved in about a month ago. We are talking a foot+ of leaves/algae on the bottom. I spent hours and hours with a trusty pole w/ leaf bag attachment. And it sucked.

We finally got someone to come open the pool correctly (that story is a post in itself). I starting looking online for how the heck to get a pool up and running as it was a green disaster. I found this forum, and it's been a godsend to say the least. I've now got both a taylor K2006 and K1000 test kit. I started on the BBB method of maintaining the pool. By BBB I mean bleach, bleach, and bleach. The pool is now *mostly* blue. There was still a lot of cloudiness in the deep and from the initial test results it seemed pretty obvious:

FC: 8ppm
CC: 1pmm
ph: 7.8
CYA: 35ppm
TA: 375ppm
CaHardness: 275

I decided to test the city tap water - its alkalinity was about 300ppm. Blech.

Now I can finally get to my questions revolving around lowering TA (yes, I've read the guide posted on these forums regarding lowering TA and now I know whey EVERYONE says it's a pain in the you-know-what).

I've been adding Muriatic Acid a couple times a day - about 48oz. at a time (20oz/10k gal) making sure to wait 6 hours or so between doses and also being sure that the ph wasn't under 7.2 when I added it. I've been doing this for 3 days and it does seems to be helping some - cloudiness is down and TA was down to 300ppm today. I'm concerned for when I do get below a ph of 7.0 ad it's been raining non-stop here and I think that has contributed to the aeration. That said.....

Question 1: I read on a different site that your pump should be off and water completely still when you add the acid to the deep end of the pool. (Link: Link removed by mod) Is this true? Seems the folks here are saying to add the acid with jets on, watch the ph and then aerate when ph is < 7.0. The link seems to think by adding the acid when the pool is still that it will change the TA without messing with the ph as much.

Question 2: Should I be adding/using borax to raise ph after adding Muriatic Acid? I haven't been able to find a definitive answer on this issue. Will borax help raise ph and have a minimal effect on re-raising the TA? I don't really have a good way to aerate the pool besides pointing the return jets upward. I've seen people mention cheap fountains but I'm clueless on how they work or which one to get. I honestly haven't searched the forums for fountain-related topics.

Question 3: I lied; this isn't a question - just a preemptive thanks for any responses!

Cheers!

First of all, welcome to the forum! Second of all, just to let you know --- I deleted the link to the URL you had so I could mod your post in faster for you.

Looks like you have been doing your homework and doing a lot of reading. Also, if you haven't already done so, go and read at our sister website www.poolsolutions.com.

The answers to your questions are pretty easy ones!

#1. ON. Always have the pump on when adding muriatic acid slowly in front of the return jet.

#2. NO. Instead of using Borax, just aerate the pH back up. Just point the return jet upward to let it make as much bubbling on the pool's surface as possible. Maybe borrow a gang of neighborhood 10 year old boys and tell them to splash away. Get in the pool (when the 10 year old boys go home) with your fiance and splash each other and make waves, etc. Lowering alk is a gradual process. It will take time, but it will work.

#3. You're welcome!

By the way, with a CC reading of 1ppm, that is a sign that you are still fighting something in the water and need to shock the pool back up again. The cloudiness is most likely dead and dying algae. Continue shocking the pool until you can go from sundown one evening until within 2 hours of sunup the next day without losing more than 1ppm of cl overnight. Then, in my opinion, shock for one more day for added insurance. Then let the cl drift down and keep it between 3-6 all the time -- based on the Best Guess table in my signature below which I'm assuming you are already familiar with.

I know you are just using bleach but just want to caution you that I would not use cal-hypo in this pool since your hardness reading is already 275. Vinyl liners don't need calcium. High pH + high calcium hardness + high TA = cloudy water.

Hope this helps. Keep us posted how things are going!

Wow quick reply and thanks!

I'll certainly keep posting updates. I can only assume that the old owners shocked using cal-hypo exclusively as there is substantial calcium buildup on the liner. The poolsolutions site is how I found this forum, so it is already bookmarked and heavily trafficked! In regards to using a fountain to aerate, do you have any suggestions on a money savvy way to use this method or if it is even worth my time? (The pool is a bit cold as the heater is defunct and it's been a crappy summer temp-wise so getting in and splashing isn't as fun as I'd like it to be). Here's hoping for warmer weather.

There are numerous 'fountain' attachments that you can use to replace one of your eyeballs. Maybe some of the other users can tell you what they've done.

But, given your high incoming TA, this is going to be a long term issue for you. There's no rush (except to keep chlorine in your pool!) but you probably should look for some permanent method of aeration on your pool

Welcome to the Forum!

Madcrammer, the high TA issue must be a Minnesota thing. I live in Lake Park, MN and am opening my pool for the first time in several years. It sounds like mine was as bad if not worse than yours. I ended up draining the whole thing, scooping out all the leaves and muck, and am now refilling. I tested my fill water which is from my well and the TA is 370 and my calcium is 400. I have an odd inground pool construction of hard fiberglass panels for the 3' side walls and then floor and entire deep end are concrete. I'm not sure if I should even attempt the TA fight.

You don't have to 'fight' it. All you have to do -- if you are not having scaling or cloudiness problems you need to resolve immediately -- is lower your pH to just below 7.0, let it rise to 7.2, and then do it again.

Well, and you need to avoid using cal hypo, which usually increases TA, though it depends on how you add it.

I use bleach or 12.5% liquid chlorine if it's on sale so I don't have to worry about the cal hypo thing. Do you think I should try to keep the ph low while I'm filling the pool or just wait till it's filled?

Actually, if you lower it AS you fill it, and arrange for your fill water to 'splash' into the pool (aerating it) you will strip quite a bit of carbonate alkalinity before you even get it full!

By the way, you do want to follow the "lower it to 7.0, and then add one more dose of acid" method. You test kit almost certainly can't distinguish 5.0 from 6.8, and a pH of 5.0 will damage things. However, if you lower it to the lowest distinguishable level (just above 6.8) you can add one more dose of acid and be pretty sure you haven't gone lower than 6.5.

Ben

How long after I add the acid should I wait before retesting the pH? I've got about 20,000 gallons in the pool right now and it holds a totally of approximately 28,000 gallons. It's not up to the return nozzle or the skimmer yet so while I have the pump running, the return is just spraying into the pool. I think that should give me some good aeration. I've stopped filling it for now so that I can spend a little time trying to get the alkalinity down. Last night I tested the pH and it was 8.2 which is the highest number on my kit. I guess it could have been higher and off the kit's limits. I added a whole gallon of acid and let the pump run and return spray into the pool all night. I just tested the pH again and it was at 7.8. This time I added a half a gallon of acid. The pump is still running. I want to test it again as soon as I should to keep on top of it. How long after adding the acid should I test the pH again? Thanks.

If you've got it circulating, you can add acid, wait an hour, and then test. If the pH is above 7.4, add more acid. If the pH is BELOW 7.2, wait another hour and test again. What you want to do is cycle the pH below 6.8, but not very much below, and then let it rise.

Ok, I just went out and tested the pH again and it was 7.5. Hmmmm, I thought it would be lower than that since just two hours ago it was 7.8 and I added a half gallon of acid. I just went ahead and added the other half gallon and will test again in an hour. Looks like I'm going to need a lot of acid.

If you are aerating effectively, you may 'consume' the acid very rapidly indeed. But be careful; as your alkalinity drops, it will take less and less acid to move the pH. You don't want to increase your doses, and then suddenly find you have a pool pH that's testing as 6.8, but is really 4.8!

Ok, thanks for the warning. What does a pH that low do? Just curious.

Damages liners; erodes concrete and plaster; corrodes metal in pool heaters.

That's enough, isn't it?

Yeah, that's plenty..lol..I don't have a liner or a heater but I do have concrete. I'll keep a watch on it. Heading to the store now for some more acid. I just checked my pH and alkalinity again. pH is 7.2 and TA is 260...I have a long way to go.

If you want a more detailed explanation of the chemistry involved in what you are doing this post can explain it.

If you want to know why slugging the acid with the pump off is bogus this will explain.

Thanks, Evan.