Total Alkalinity recommendation from pool store

[tmgoethe]

I just got the water checked at the pool store and they are trying to get me to raise the total alkalinity to at least 120 for a salt pool. The pool is an Intex above ground 15x48". The recommendations here are for 60-80 which is what I was shooting for by aerating the water. I'm curious why the recommendations are so different. They were disappointed when I didn't buy the alkalinity increaser. I did buy some other stuff, so not a loss for them.

I have had issues getting it to clear up, but think I am almost there now. I believe that some of the pool store advice (using nothing but trichlor tablets and then a copper algaecide) were not helping much.

I was also checking my tests with my new TFT kit as well as getting a salt readout as I am about to start the salt generator and, as yet, don['t have a way to check salt levels.

My readings vs. theirs were:

Mine
TC 7
Ph 7.3
FC 6
CC 1
TA 100
CH 230
CYA 40

Theirs
TC 4
Ph 7.4
FC 4
CC 0
TA 110
CH 290
TDS 3,200
Salt 2,200

Thanks in advance!

 

[duraleigh]

PLEASE trust your own testing and disregard pool stores. Nobody cares more about accurately testing your water than you do. I can't answer why the pool store doesn't agree with you but trust that tool you have in your possession....it works.

PS - keep your TA where it is unless the pH is rising rapidly. If it is, lower TA to 60-80ppm.

 

[Butterfly]

Yep, always trust your own testing! Forget the pool store #'s.

Based on your tests, you have 1CC and still need to continue the shock process until you meet the three criteria that determine you are done shocking.
See red lines in my sig.

Have the pool store test your water for copper levels. Copper is the only thing that turns blonde hair green and can make impossible-to-remove stains.

Don't use any more of the copper containing algaecide. In fact, the only algaecide we recommend is PolyQuat60 - then only usually for closing pools or doing an AA treatment. Algaecides are not needed in a properly chlorinated pool.

Once you are done shocking, you should raise the CYA level up around 70-80.

 

[tmgoethe]

Thank you both! It has been a frustrating year for this pool. Last year was pretty easy, but this year it didn't want to clear. I had used, as last year, about 2/3's well water from my iron rich irrigation well and 1/3 utility water. Last year, the iron went yellow when it hit chlorine, fell out and I vacuumed a lot of it up. I then used Natural Chemistry Metal Free and a clarifier (forget brand) and it looked quite nice at about two weeks or so into it. I was initially using bleach and Calcium Hypochlorite pool shock until I added an Intex salt to chlorine generator. This system worked well until October when some algae started trying to come in and I was ready to take it down anyway.

This year was very different. Some of it was my fault. I had gotten a deal on some pool shock, calcium kind, and used that for all my chlorine. I also used the Metal Free and clarifier, but it took about three weeks to even begin to start to clear. It was a yellow, green color. I did work the ph down with some powder, forget the brand and did add stabilizer.

I went to the pool store for help and they blamed the use of pool shock on the cloudiness which probably has some validity based on what else I've read since. They put me on trichlor tablets, however, as the main source of chlorine and the stabilizer rocketed. They also had me add acid to get the ph down which was probably right. They also sold me liquid chlorine to shock with.

Next, my six-year-old and a friend got into it after using a bunch of water color paint, and it was back to murk. After another week of cleaning, it started to clear again, but we went away for three days. I left the chlorine level high, but since I was using test strips, I am not sure how high it really was. When we got back, it was green and very murky. I gave it a lot of chlorine and went to the pool store. They said keep shocking and sold me the copper algaecide and clarifier.

After about four days, it still looked awful, so I dumped about 3/4's of the water and refilled with utility water. I also enlarged the holes for the strainers so I could get better water flow. This one had the 1 1/4 inch hole. The old one had 1 1/2 inch holes. Then I found this site and things here seemed to make sense (also gave me courage to cut that liner!). I had been having flow issues with the salt generator and the bigger holes did the trick. The 2,500 gph pump had been stalling, so I was using a 1,500 gph one. I went back to the 2,500 gph filter pump and verified the generator would work, but wanted to get the water a little better before running it.

I also bought the TFT test kit.

When the CYA came down substantially after dumping the water, I figured I would use up the remaining trichlor tables to get the CYA back up to a reasonable level. I also figured the dump would get rid of most of the copper.

I have been trying to keep the chlorine high, but slacked off a bit the last couple of days. I also had several kids in the pool and a lot of rain yesterday. I'll nuke it tonight.

I did use a polymer based algaecide along with a flocculent. The flocculent really helped drop stuff to the bottom, but I don't have a way to pump to waste other than in my yard. I'm going to come up with a solution for that. Since it was going through the filter, about half of it stayed in the pool, but it is much, much better after three nights of settling out and vacuuming. I also gave it a maintenance dose of the Metal Free which supposedly will take out copper as well as iron.

I got the salt generator going today and took advantage of the Wal-Mart deal on the Intex 14" 1,600 gph sand filter pump someone posted in another thread. It sounds as if that will be an improvement over the cartridge filter.

Beyond that, I hope that watching the numbers on the water and nuking it with chlorine will get it the rest of the way and keep it nice.I am thinking about the Boraxo/acid treatment too.

Thanks again and if you have time, suggestions would be appreciated.

 

[JasonLion]

Metal Free is not one of the sequestrants we recommend. Sequestrants based on HEDP, phosphonic acid, or phosphonic acid derivatives are much more effective. Sequestrant does not usually remove metals from the water. Mostly they just bind to the metals and prevent them from staining until the sequestrant breaks down, at which point the metals are back in the water.

You shouldn't use flocculant if you can't vacuum to waste. You might get the water clear for a few days, or even weeks, but everything is still in the water and will just return and need to be dealt with again as the floc breaks down. In the meantime the floc can be a skin irritant.

We don't recommend using algaecide except in special situations. As long as you maintain appropriate FC levels there is no need for it, and some kinds have negative side effects.

It isn't a good idea to swim with CC above 0.5. CC can cause skin and eye irritation.

 

[chem geek]

I just got the water checked at the pool store and they are trying to get me to raise the total alkalinity to at least 120 for a salt pool. The pool is an Intex above ground 15x48". The recommendations here are for 60-80 which is what I was shooting for by aerating the water. I'm curious why the recommendations are so different. They were disappointed when I didn't buy the alkalinity increaser. I did buy some other stuff, so not a loss for them.

The people at most pool stores do not understand water chemistry. They often just parrot what they are told by chemical sales manufacturer reps and that information is most often designed to maximize sales. This is why they intentionally withhold materially important information that pool stores and pool owners would need to know to make informed purchase decisions to manage their pools inexpensively. They do not, for example, disclose the following chemical facts that are independent of concentration of product or of pool size.

For every 10 ppm Free Chlorine (FC) added by Trichlor, it also increases Cyanuric Acid (CYA) by 6 ppm.
For every 10 ppm FC added by Dichlor, it also increases CYA by 9 ppm.
For every 10 ppm FC added by Cal-Hypo, it also increases Calcium Hardness (CH) by at least 7 ppm.

They do not disclose the chlorine/CYA relationship and its importance to preventing algae. They do not disclose that TA is a source of rising pH in its own right so the TA should be lowered, not raised, in most situations when the pH tends to rise.

 

[tmgoethe]

Thanks all!

I did clean about half the bottom into the yard today, so that stuff should be gone for good. I know the filter is catching some of it, but not the majority. When I get the sand filter and know what sort of connection is has for a waste hose, I will get a hose so I can dump it in an area where I don't mind losing lawn.

I will stop with the Metal Free and polymer algaecide. I was shy of the sequestrants that have phosphorous. I had been getting horror stories on phosphorous at the pool store. I realized that as it breaks down, it will come back. My main hope at this point was to take care of whatever copper was left from the first algaecide.

I gave it a shock this afternoon and it seemed to get slightly cloudier. Would that be from killing some more algae? I do notice that the water from the return is cloudy when the Intex generator is running, but assumed that was from chlorine bubbles. The CC was zero when I tested it just before dark, so hopefully that is progress.

Thanks again everyone.

Thanks again