Phoenix CYA levels

Feb 8, 2018
8
Phx, AZ
#1
Moved to N/W Phoenix, fired my pool guy after he yelled at me for letting my dogs swim in MY POOL.... Then I found this site and now have already gotten my hands dirty!!

Got my TF-100 test kit and speedstir a few days ago.

First numbers:
FC 4.5
CC 1.5
CH 550 (AZ water...)
TA 90
CYA 30
PH 7.5 ish...
Temp: cold!! 55 ish

The water is clear but does have a little chlorine smell.

Water was room temp when tested.

My questions are should I slam due to 1.5 CC and should I increase my CYA to around 60-70 due to the hot summers?

Another question. Do you guys take your water sample while the water is circulating, or is it ok to take it when the pumps are all off. I currently have my pump set up to run from 9 PM till about 8 AM. And do you take the sample at the same time of day?

I would like to get the pool set up now, cause this winter is really warm and pool weather seems right around the corner.

The pool water was changed fall 2017 and the hardness is high, cause we have very hard water here. Funny, the local pool places both said my CH was around 300. I got a flash of blue around 300 with the TF-100 test kit then it went back to pinkish. I tried putting in reagent R-0012 first as was indicated in another thread, but it still read about 22-25 drops to turn blue (tested it 3 times!!)

Thanks in advance!
 

mknauss

Mod Squad
May 3, 2014
11,885
Laughlin, NV
#2
Welcome to the forum!

Good job on getting a quality test kit.

I would suggest you do an one night soon. You may need to but doing the OCLT will confirm.

Wait until you confirm your need to SLAM before raising your CYA. It sounds like you will be using liquid chlorine DAILY to chlorinate so in March sometime you can take your CYA to 50 ppm.

Odd that your CH has jumped to that level if you replaced your water last fall. I would suggest taking a fill water sample and testing for pH, TA, and CH for a baseline.

It is best to take the water sample after about 30 minutes of circulation.
I doubt you need to circulate your water that much. Read Pool School - Determine Pump Run Time

Eventually you may want to consider adding a SWCG. Makes life much easier as far as pool water maintenance.

Take care.
 
Feb 8, 2018
8
Phx, AZ
#3
Thanks for the quick reply.

Yes, im using 12.25% liquid chlorine from pool store. And Using 31.45% MA for PH control.

Im renting the house. I have no clue what the water was like before I moved in (Oct 2017)

Ill test the water from the backyard hose to and see what the results are.

Ill do the overnight loss test tonight and post results.

As far as the pump runtime, We had a huge algae problem a few months ago. So I run the pump longer than I need to to prevent another mess....

I considered going to salt, however im not sure if the landlord would let me, and even then it would be a waste of $1200 cause I cant take it with me.

And just to clarify. I had the water tested at 2 different pool stores this week, before I got the test kit. So they said my CH was around 300. Not sure if off, or they are. so, well, I dont know..
 
Last edited:

slickraft

Well-known member
Oct 7, 2016
219
Phoenix
#4
I keep my CYA around 50 but some owners here in the desert SW (well experienced pool owners) go much higher. Just follow the recommended TFP method for now and don't try to experiment just yet.

I sample from a corner step area when the circulation happens to be off. I like to know how my water is doing under the worst case conditions so I test at the end of the day when the sun has been beating down and when it has been a few hours since the pump was on. If my water is good under those conditions, I know it is no worse at any other time of the day.

I made my own chlorine pump system that doses chlorine 2 times a day when the pump is running. I use 10% Home Depot chlorine and add acid manually as required. I initially fill my pool with city water but have a soft water line hooked to my make-up water valve. My pool is 12,000 gallon play pool and quite easy to maintain after finding TFP.
 

Jimrahbe

Mod Squad
TFP Expert
LifeTime Supporter
Jul 7, 2014
10,209
Bedford, TX
#6
2bl,

Welcome to TFP... a great place to find the answers to all your pool questions, whether your dogs swim in the pool or not... :shark:

You can't just talk about your dogs swimming... we need pics.. :p

Sounds to me like you are well on the way to having perfect pool water. Good job on getting the right test kit..

Glad you found us.. and thanks for posting,

Jim R.
 
Feb 8, 2018
8
Phx, AZ
#7
Ok, here are todays test results.

The pool water FC is 2.5
and CC is 1

I used the TF-100 test kit and R-0870 and R-0871 reagents for the test.
i didnt bother with any other tests.

Im assuming I should SLAM, yes, no?

I also tested the fill water from the backyard hose.

FC 1
CC 0
CH 500 (so im assuming my results are not wrong)
TA 130
CYA 0

I went to the city website for the water report and they ad one from 2016. The Hardness (didnt specify exactly if it was chemical or what) of the water was 10 Grains/Gallon. So we just have really hard water here. Im not sure how much high CH will throw off readings, or make it more difficult to adjust pool chemistry.

Thanks,

and Ill post pictures as soon as I get a chance to figure out how to post pictures.
 

mknauss

Mod Squad
May 3, 2014
11,885
Laughlin, NV
#8
Is your FC test from an ? If so, did you do a FC reading last night and the one this morning before the sun shined on the water?

10 grains per gallon is not all that hard. Our water here in Laughlin (Colorado River water) is 17 grains per gallon. Equates to about 250 ppm CH.
 

needsajet

TFP Expert
LifeTime Supporter
Jan 5, 2016
4,548
Sydney, NSW, Australia
#10
Just in case... the calcium test is a 10 ml sample (lowest line).

BTW, I can tell by your post you got this. Glad your dog gets to swim, hahaha, that's funny about the less-than-confident pool guy :)

Welcome to TFP!
 
Feb 8, 2018
8
Phx, AZ
#11
Good morning.

Ok, tested last night and this morning. Got 1.5 FC reduction. According to the stuff I read here I should SLAM.

Readings.

2/14/18 1830 FC 5.5
CC 1.5

2/15/18 0730 FC 4.0
CC 0.5

And yes, Im using 10ml of water as my sample size for the CH test.

My water system is as follows.

Street- Meter- Regulator- Outside hose tap (where i sampled from) - Irrigation tap- /inside house/ water softener- splits to water heater and to whole house.

So my sample was before any water processing in my house.

I still think the water in this area has a high CH. The results I found online were from 2016. The next towns over had higher hardness numbers.

But lets just say my CH was high because of my pool. What downsides could this have? Structural damage to the plaster, cosmetic damage, just bad overall, what does it actually mean? What could cause this? Is it something my pool guy could have done? Plaster leaching from my pool? I know the pool is plaster and the owner changed the water in either September or early October 2017. And were in Phoenix, so it was hot and im talking around and above 100F. Could they have messed up the plaster if they drained the pool and it was too hot?

Overall I have a pretty good handle on what I need to do. Ill up my CYA to protect my FC after I slam and other than that I think I should be good to go!
 

mknauss

Mod Squad
May 3, 2014
11,885
Laughlin, NV
#12
SLAM away. Get 30 ppm CYA in the water now. You cannot SLAM with 0 CYA in your water.

We all here in the desert SW manage high CH. You need to manage your water with an eye on CSI. It is calculated in PoolMath and in the App. Keep it between -0.6 and 0.6 and you will have few problems with calcium.

You will, however, be changing your water out often if your starting CH from your fill water is 500. You will essentially be needed to change your water every year. You might investigate to see if your water softener can supply your make up water (not initial fill) to reduce your CH rise.

Let us know how the SLAM goes. Be sure to get your pH down to 7.2 prior to starting your SLAM. You will not be able to test pH during the process as your FC will be above 10ppm.
 

triptyx

TFP Guide
Apr 12, 2016
1,485
Tucson, AZ
#13
The water in Southern Arizona is extremely hard. It is known. :)

We also have a very high evaporation rate due to the very dry air, which means the calcium in the water is concentrated over time as water evaporates out and new, high CH fill water is added. It's possible the pool company and/or previous owners were using cal-hypo shock, which would also add calcium. Sticking with bleach or liquid chlorine to shock will mitigate that problem - we definitely don't want to add additional calcium to our water here!

High CH will result in scaling at lower pH's than water that is in the recommended TFP range. You can watch your CSI number and manipulate your pH and TA (though make sure you're keeping pH between 7.2 and 8) to keep your CSI near or slightly below 0 to avoid scaling risk. Scale can cause some issues with your pool heater if you have one, but otherwise, if you're keeping your CSI in line, you can do fine with higher calcium levels.
 
Feb 8, 2018
8
Phx, AZ
#14
Yeah, I was wondering how much water I will lose to evaporation. The pool has an autofill so im not really paying attention to it.

My current CYA level is 30, tested about 3 days ago. Ill add MA today and drop my PH to 7.2 then start the slam later today.

I plan on using liquid chlorine, unless I go away, then ill throw a few pucks in the skimmer.

Thanks Marty, Ill keep an eye on that level. I know there are a few companies in the area that do a "water exchange" they come in and do a RO or softener process to get the chemistry back to normal.

What drives me nuts, and why i have to run the filter for so long, is all the stuff that ends up in the pool. Our yard is rock and all this sand and dirt end up collecting in the pool. Even with the floor cleaner I still have to brush the pool every 2-3 days so it gets taken care of.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,344
Tucson, AZ
#16
Dead algae can often look brown like sand. When you brush it, it will puff up into a cloud, disappear and then settle somewhere else. Given that you're about to SLAM the pool, your sand issues may actually be algae issues. Usually if you have enough rocks around your pool, the sand is minimal unless neighbors around you don't rock their yards. I very rarely see sand in my pool but my robot definitely catches lots of silt with the fine filter installed.

Historical pan evaporation data can be found here - http://www.patagoniaalliance.org/wp-content/uploads/2014/06/ARIZONA-MONTHLY-AVERAGE-PAN-EVAPORATION.pdf

You can expect that your average evaporation loss for the year will somewhere north of 90" of water (probably closer to 100") with the majority of that loss occurring between April and October. The peak is usually between June and July with a rate of almost 1/2" of water per day. In my pool, that works out to nearly 140 gallons of water per day or an additional 5 CCF per month. Since the average annual total is above 90", that's pretty much the entire volume of water for a typical sized swimming pool. So, if you measure your fill water CH, then that CH value will be close to what you can expect your pool's CH to rise every year.

After 4+ years of this, I'm seriously looking into a water softener with a hook up to my pool fill line and/or installing rain barrels to capture rain water off my roof. The one section of my roof in the backyard by the pool easily sheds hundreds of gallons of water everytime we get a good rain. In fact, it's been raining here since yesterday and my water level is about an inch below the coping. I plan to throw a submersible pump in the deep end to try to draw off water.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,344
Tucson, AZ
#18
I cry a little every time it rains. This is from just one section of my roof nearest the pool -

[YOUTUBE]https://youtu.be/bpXkBpNaZ6I[/YOUTUBE]

I have three other downspouts like this. A few good storms and I could refill half my pool.
 
Feb 8, 2018
8
Phx, AZ
#19
Ok, wow, Joyful you nailed it. We had a ton of algae back in October. Pool guy cleared it up. BUT there was that brown stuff on the bottom of the pool. So I thought it was just dirt! WRONG.... I SLAMed it last night. The brown stuff is gone!! Im really happy! Thank you guys so much.

My reading tonight was FC 13 and CC 00!! Ill run the filter for the next few days to suck up all any thing else in the pool.

Im going to head to the pool store to get stuff to raise my CYA. Im going to use the granular stuff. Ill check my level in a day or two when the chlorine gets down to about 5 or so. I think I should run my CYA at 50 or 60. what sez you guys?

And a sidenote about the evaporation. I didnt realize how much pool water we lose in the summer! That is amazing. Then I think about looking at the Arizona canal. It pains me to think about how much water is lost from evaporation along the whole path.
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,344
Tucson, AZ
#20
Welp, as the old saying goes, even a broken clock is right twice per day :lol:

Glad your SLAM is going well. You'll be crystal clear and algae free before you know it.