First results with TF-Pro

[LARichardson]

Hey everyone. I am new to the TFP forums. I posted about a week ago with my initial problem, which I mainly saw as low pH and high Alkalinity (High Alkalinity, Low pH. Aeration.). Other users replied, telling me that I probably had bigger problems, and that the first step was to get a dependable test kit. So, I got a TF Pro, and ran my first tests:

FC - 7ppm
CC - 0
TC - 7ppm
pH 7.3
TA - 160
CH - 1,125*
CYA - 400**

*CH test was modified, because the solution was not turning blue. I added 8 drops of R-0011L, instead of 3. Adding 45 drops of the R-0012 turned the solution blue.
**CYA test required a 3:1 mix of distilled water to pool water in order to get a reading anywhere close to 100. It was actually a little higher than 100, but I just went with 100 and multiplied by 4.

So, any advice is appreciated. I guess the first thing I'll have to do is either drain/refill or get an RO treatment. I'm considering the latter, as water in these parts is precious.

 

[Texas Splash]

Good news & bad news. Good job on testing your water wiht a proper test kit. The bad news, you'll really want to exchange some water. While it's certianly common for AZ's to have an elevated CH level, your CYA is well past the manageable mark. Before the sun gets crazy hot over there, would you be able to do a water exchange? That would certainly resolve yoru CYA issue. Of course your fill water may be hard as well, so your CH may still shoot up to 600 or so, but hopefully not over 1,000.

Good thing is your low pH helps to compensate for that crazy high CH.

 

[LARichardson]

I’m looking into R/O. If anyone has a company in the Phoenix/Mesa AZ area they could recommend, that would be great.

 

[Newdude]

OK so peep this chart.




You'll notice that minimum is give or take 8% of the CYA level. At 400, your minimum FC is 32. Algae and far worse things can flourish anytime the FC dips below 32, and your current level of 7 isn't going to scratch the surface.

But see what a difference a reliable kit makes? We know right away what's going on and what to do about it. Well done.

 

[an1vrsy]

Do you have a whole house water softener system? If so, you can get a line plumbed off of it to use for your pool‘s auto fill line. Without thinking about that now, you will have high CH in a year or two. Colorado river/municipal water is pretty hard.

 

[clambert1273]

I’m looking into R/O. If anyone has a company in the Phoenix/Mesa AZ area they could recommend, that would be great.

I sent you a message on here

 

[LARichardson]

Do you have a whole house water softener system? If so, you can get a line plumbed off of it to use for your pool‘s auto fill line. Without thinking about that now, you will have high CH in a year or two. Colorado river/municipal water is pretty hard.

Yeah, we don't have a water softener. I guess I'm prioritizing the CYA level at this point. I just want to get that down. I know the Ca will come back up.

 

[LARichardson]

Good news & bad news. Good job on testing your water wiht a proper test kit. The bad news, you'll really want to exchange some water. While it's certianly common for AZ's to have an elevated CH level, your CYA is well past the manageable mark. Before the sun gets crazy hot over there, would you be able to do a water exchange? That would certainly resolve yoru CYA issue. Of course your fill water may be hard as well, so your CH may still shoot up to 600 or so, but hopefully not over 1,000.

Good thing is your low pH helps to compensate for that crazy high CH.

Texas Splash. I am looking at either hiring a company to do an R/O treatment, or doing a no drain exchange. I have a few questions I was hoping you folks at TFP could help me with:

- The R/O companies I have contacted are asking me for the TDS. The instructions for a no drain exchange on TFP also mention TDS, in order to calculate DeltaT. But I'm not sure how to measure or calculate this number (TDS). TFP seems to say that most measurements are suspect.

- Given that my CH is over 1000, and CYA is 400 (best I can measure), would it be safe to assume that I would drain from the deep end and fill from the shallow?

- Given how high the CYA level is, is it realistic to think that a no drain exchange will be effective in bringing this level down within recommended range? With a number that high, I think I have to drain at least 95%. There will probably be a fair amount of mixing of old and new water. Would I just need to run the drain/refill for longer? My pool is 13,100 gallons. So I would just run it long enough to pump out 15K gallons.? Does that sound right?

I am not planning on doing this immediately. I am new to all of this, and will need time to plan. Thanks for any advice you could give. People on TFP have been really helpful so far.

 

[Texas Splash]

You have the right concept all around. It's a major water exchange for sure. Ideally, ripping the band-aid off quickly for a 100% exchange is ideal, especially with your CYA, but some folks can't do it for various reasons. TFP doesn't generally get wrapped up around the axel on TDS, but since you asked, I'll see if @JoyfulNoise can contribute to help clarify some of your concerns in that area.

This link may also help.

Draining - Further Reading

www.troublefreepool.com

 

[LARichardson]

You have the right concept all around. It's a major water exchange for sure. Ideally, ripping the band-aid off quickly for a 100% exchange is ideal, especially with your CYA, but some folks can't do it for various reasons. TFP doesn't generally get wrapped up around the axel on TDS, but since you asked, I'll see if @JoyfulNoise can contribute to help clarify some of your concerns in that area.

This link may also help.

Draining - Further Reading

www.troublefreepool.com

Thanks. If it wasn’t getting so hot here, I would probably think about draining and then filling, instead of a “no drain” method. But by the time I am ready to do it, it’ll probably be too Dang hot.

 

[Newdude]

Any pool store can test your TDS. It should be accurate enough for what we need to know.

 

[JoyfulNoise]

If you can give me a full set of test results -

pH
FC
CC
TA
CH
CYA
Salt

I can calculate the TDS for you.

 

[JoyfulNoise]

RO isn’t really going to be worth it. Even here in Arizona where water is more expensive than silver, it’s almost always cheaper to drain and refill. If you can rent a trash pump from Home Depot and drain the pool fast (you need a drain area that can handle a huge flow of water) and do it when the sun goes down and start refilling right away, you may be able to beat the heat. But there’s risks with that. Usually you want to drain either in November or in March/April. Not any other time of the year.

 

[LARichardson]

If you can rent a trash pump from Home Depot and drain the pool fast (you need a drain area that can handle a huge flow of water) and do it when the sun goes down and start refilling right away, you may be able to beat the heat. But there’s risks with that. Usually you want to drain either in November or in March/April. Not any other time of the year.

@JoyfulNoise

Yeah. I don't think I want to take those risks. I'm new to this. Also, I'd be going into the clean out in my front yard, so I don't think I could drain that fast.

But if I do a "no drain water exchange", the heat doesn't matter right, because the water level is maintained?

I just followed the link in your sig, and that you have done the no drain method before. This is why I'm trying to figure out the TDS, because it seems I need that in order to see which side to drain from and which to fill from? I have all the results you asked for in your previous post, except for the salt level. I don't have a salt test kit. I guess I'll have to purchase one, or get the TDS done at the pool store.

Thanks again for the info.

 

[Newdude]

But if I do a "no drain water exchange", the heat doesn't matter right, because the water level is maintained?

Correct.

 

[LARichardson]

@Texas Splash @JoyfulNoise @Newdude

I was wondering if I could ask you guys a few more questions.

I am planning on doing a no drain water exchange, hopefully early next week. I got a submersible pump. I know where I am going to drain the water (clean out). I tested both my pool water and fill water this morning, and this is what I got:

Pool water:
temp - 74
FC - 9.5
CC - 0
pH - 7.6
TA - 190
CH - 1225
CYA - >400
salt - 3200ppm

Fill water:
temp - 89
FC - 2
CC - 0
pH - 7.5
TA - 140
CH - 275
CYA - 0
salt - 600ppm

First, some of the results surprised me. Namely, the FC of the fill water, and the salt of both the pool water and the fill water. But I repeated each of these tests and got the same results. I used the Taylor K-1766 test for the salt levels. I was also a little surprised at the CH of the fill water. I thought it would be higher. Are these unusual results?
Second, I think I can conclude from these results that I am going to drain from the deep end and fill from the shallow end (the step, using a bucket). But just for the sake of doing things right, I'd like to understand how to run the formula listed on the "Draining" article on TFP:

"Replacing water in-place process depends on several factors:[4]

• Pool Water TDS (PWTDS)
• Pool Water Temperature (PWT)
• Fill Water TDS (FWTDS)
• Fill Water Temperature (FWT)

DeltaT = (PWT - PWTDS / 165) - (FWT - FWTDS / 165)

If DeltaT is positive, then you want to fill at the lowest point and extract at the surface and at the greatest distance from the lowest point.
If DeltaT is negative, then you want to extract at the lowest point and fill at the surface and at the greatest distance from the lowest point. <-Preferred as it is easier to do with a drain pump and you can fill inside one of the skimmers."

So, could anyone explain how I calculate DeltaT from the test results I got today? I just don't know what the PWTDS and FWTDS values would be.

Thanks so much.

 

[mknauss]

Add the salt and CYA together and you have an approximate TDS.
Check your fill water temperature. I suspect if you run it for a few minutes it will cool off.

 

[LARichardson]

Add the salt and CYA together and you have an approximate TDS.
Check your fill water temperature. I suspect if you run it for a few minutes it will cool off.

Yeah. I actually let the hose run for roughly 5 minutes, then filled a 5 gallon bucket and temped that. I'll try it again to double check.
Thanks for the info. If these results are correct, it looks like I'll get a result far in the negative. So, I'll drain from the deep end and fill from the shallow, and should get a good exchange.

 

[mknauss]

Your water lines likely go through your attic. So you need to get the water to flow enough to get it from the street. That water is likely cooler at this time of year.

 

[LARichardson]

Your water lines likely go through your attic. So you need to get the water to flow enough to get it from the street. That water is likely cooler at this time of year.

I ran the hose for 20 minutes before temping today, and it still came out the same. 89. I'm a little surprised, but, this IS Phoenix after all.