First time TF-100 Test: Post AZ Haboob Cleanup

[nickazpool]

Hello and thank you for all of the great information on this site. First I wanted to post my pool's background, this is my first time owning a house with a pool and I purchased it a year ago. It is a Salt water pool was a SWG, 20,000 gal. I've been using a basic FC/pH test over the last year and adjusting my SWG's levels accordingly and everything had been great until our recent "Haboob" that blew a ton of dirt into our pool (Arizona, might have heard about it as it made national news). Prior to this the pool has always been crystal clear, can see the 9' deep end without any issues. Immediatley after the storm I couldn't view my hand 1' foot down due to the dirt, however after excessive running of the pool filter and my cleaning of the filter multiple times the pool is 100% clear again.

My Issue: Little green circles about half the size of a dime and smaller started showing up on the bottom of the pool, mostly on the steps and the shallow end. After visiting your site I believe I was testing my FC at the wrong time of day and sun was killing my FC level during the day which allowed these alge circles to grow, most likely deposited by the storm. This time of year I run my filter 10 hours a day, and have had my SWG at 100% over the last week. Prior to the Haboob it was only at 60%.

Reading your site also prompted my ordering of the TF-100 and results below, measured at 6:30 PM after a full day of sun.

FC: 2.5
CC: 0
TC: 2.5
pH: 7.8
T/A: 50
CH: 600+
CYA: <20, could easily see the black circle when vial was full
Temp: 89

My quesiton is what should I address first? I am concerned about the CH reading, after adding 60 drops I still see little red circles floating in the test solotion but the background color has shifted to a slight blue hue, but I've had no symptoms of too high CH in my pool? Could this be a new issue from the Haboob dirt?

I'm assuming I should address the CYA level and T/A level first, to bring both up to ~70. Should I do this in a specific order? All at once or gradual? I also think I need to shock my pool more throughly, being at 100% over the last week has started reversing the hold but it hasn't completely solved the problem. I'm not sure what shock level I should aim for?

I haven't started using the BBB method yet as I was waiting for my test kit to arrive first. Prior to now the only additive I've ever added is muriatic acid to control PH.

Thank you for your time and advise,
-Nick

 

[JohnT]

Welcome to TFP!

You have two significant issues, both related to your location. First is your CH. Most fill water in your area is very high in CH, and with the heat and sun you have, you have high evaporation which causes you to need to frequently add more high CH fill water. Reverse osmosis treatment may be available in your area, and is worth considering. In the meantime, you'll want to work on keeping your pH in the lower end of the range.

With very low CYA, your pool will struggle to maintain chlorine levels on days when the sun is bright. In your area, 50ppm might be a reasonable number to work with. But if you choose to go with the reverse osmosis for CH reduction, it will remove your CYA as well.

 

[Butterfly]

I haven't started using the BBB method yet as I was waiting for my test kit to arrive first. Prior to now the only additive I've ever added is muriatic acid to control PH.

Sure sounds like you have started!...got a SWG and only added MA!

Yes, we saw the Haboob on the news

Suggestions:
1. You can increase the TA to 60 or 70 using baking soda, then lower pH to 7.2ish with MA
2. Add enough CYA to increase 30ppm(for now). I am assuming since you can clearly see the dot, CYA is zero. Use the sock method to add the CYA. 24 hours after adding the CYA, increase shock level to about 12. Directions for How to Shock Your Pool are in Pool School.
3. Start the shock process using FC shock level of 10. Use bleach/liquid chlorine for shocking.
4. Turn off SWG and give it a rest!

Use the PoolCalculator.com to figure doses.

Try this with the CH test:

If you expect that your CH level is extremely high, you can do the test so that each drop is 25, instead of 10, to speed up the process and save on reagent usage. Use 10 ml of pool water, 10 drops of R-0010, 3 drops of R-0011L, and multiply the number of drops of R-0012 by 25 to get your CH level

From Extend Test Kit Directions: extended-test-kit-directions-t25081.html

Post back in this thread with any q's.

Congratulations on your new test kit

Welcome to the forum

 

[nickazpool]

Thanks to both of you for the advise on the way to tackle my issues.

I tried the modified method of testing CH and it is at 675, what are the downsides of such a high CH? From JohnT's post it sounds like this likely was an issue before the Haboob, just want to know if I'm able to put off resolving this problem or if I should jump on it as it sounds like I'd have to hire someone to do RO on the pool to resolve it since my fill water has high CH as well.

I'll let you know how it turns out and if I have any further questions in implementation of the CYA additions and shocking the pool.

-Nick

 

[Butterfly]

What is the CH in your fill water?

 

[nickazpool]

Using the 25 per method, I just tested it at 150 for CH.

 

[Butterfly]

Using the 25 per method, I just tested it at 150 for CH.

Sounds good. So, it sounds like the CH of 600+ is a result of the Haboob and over time (okay, maybe a long time) with splash out, rain and fill water being low in CH, it will come down.

Let others chime in w/ an opinion on which way to go, but I'd just work with it as is.

 

[Steve456]

High CH can cause calcium deposits on your SWG cell. Use the Pool Calculator to adjust your pH so that you maintain a CSI Index of 0.

 

[Swimgirl]

I live in pretty close to the same area. Had haboob problem too. I live in a rural area, though, so I do get some dust deposited in the pool even by smaller wind storms. I seem to always have a least a little dust in the pool most the time during monsoon season, that light talcum powder consistancy stuff that floats when trying to vacuum it.
I don't have a SWG. Just use liquid chlorine. I myself try to keep CYA of 40ish, or even higher. Much lower, I seem to lose too much chlorine. I also know that higher CYA is recommended for salt generators.
Like you, I also have fairly low calcium fill water. Since I have an above ground pool, I didn't have to add any calcium, and have only gotten some added calcium through occasional use of cal-hypo for chlorination. I will say this: since we don't get enough rain for any overflowing of the pool, and evaporation doesn't get rid of any extra calcium, you would be relying totally on splash-out to get rid of your water with too much calcium. I would say to get rid of some of the water. It doesn't have to be all at once; say, maybe about 6" to 1' at a time and then refill until your calcium is where you want it. Depending on your filter, you can just backwash longer than usual, vacuum to waste, pull the plug if you have a cartridge, etc. That's how I would do it, anyways.