Filter, Organic Material, and Chemical Service

[Uncle Flappy]

Greetings. This is my first post to this forum and I have two issues for which I could use some advice. My 30,000 gallon in ground pool uses a Pentair Triton II TR-100 sand filter and I run the pump 12 hours per day. I also use a clarifier after every backwash as it seems to help keep the water looking clean and clear. The sand was replaced one year ago. My questions:

1. I can go for weeks or months without backwashing and the pressure gauge never seems to rise. I've replaced the gauge with a new one in the event it was faulty but no change. Shouldn't I see pressure increase when it is time to backwash?
2. When I go for a week or two without brushing the sides of the pool, green splotches can appear mainly on the walls but the water is still sparkling clear. I've had the water tested and chemical levels are optimal. My service claims that this is just organic material "since it brushes away easily" but I am not convinced. Is there any truth to this or can it be an algae bloom? They also say to run my filter longer including 24x7 for the next several weeks during the rainy season.

I appreciate your feedback.

- Flappy

 

[borjis]

1. yes the pressure should increase. mine takes about 2 months to go up 2 psi

2. you don't have enough chlorine to keep the algae away, you need to post your test numbers to determine what your cya is and this will indicate what your chlorine should be.

Pool store results won't be satisfactory...do you have a Taylor K2006 or TF test kit? if not, you should get one asap.

If the pool store results indicate levels are optimal, there would not be an algae problem....so those results are no good as you can see.

 

[Uncle Flappy]

1. yes the pressure should increase. mine takes about 2 months to go up 2 psi

Should I backwash every few weeks or wait until I see an increase on the pressure gauge? Right now I am doing it about once per month.

2. you don't have enough chlorine to keep the algae away, you need to post your test numbers to determine what your cya is and this will indicate what your chlorine should be.

Pool store results won't be satisfactory...do you have a Taylor K2006 or TF test kit? if not, you should get one asap.

If the pool store results indicate levels are optimal, there would not be an algae problem....so those results are no good as you can see.

But is it algae or "organic material" as my service provider states? Is there a difference or is this just whitewash? I'll order the kit and post numbers in the next few days.

Thanks for your help!

- Flappy

 

[duraleigh]

Shouldn't I see pressure increase when it is time to backwash?

Sort of.....a pressure increase of 25% would indicate time to backwash. No increase means no backwash needed.

My service claims that this is just organic material "since it brushes away easily" but I am not convinced.

You have good reason not to be convinced. Of course it's just organic matter.....that's all algae (and germs and bacteria) is!

Get your kit and post your numbers. read "The ABC's of Pool Water Chemistry" up in Pool School. You will learn more in the next few days than in a lifetime of listening to "pool guys".....we promise.

 

[borjis]

A "green splotch" sounds like algae to me.

When I was first getting started about a year ago, I removed the chlorine tabs the previous owner had in the skimmer, but
for some reason (dumb on my part) I didn't begin chlorinating with bleach. 1 week later I too had green splotches randomly
on the pool walls, yet the water was clear.

your off to a good start getting the kit. in the meantime you might want to add at least 1 possibly 2 gallons of bleach every day
until the kit arrives to help it not get worse.

Read up on the SLAM procedure here, you will be doing that to deal with the algae problem. While doing the slam
the pump should be run 24/7 to clear out the plumes of white that will surely get in the water when you brush
the pool daily.

Your filter generally needs to be back washed when it rises 8 psi over the nominal psi.
nominal being the psi as it reads right after a backwash.

When I did my last slam, I chose to backwash it 3 different times even though it never got to 8 psi over.

 

[Uncle Flappy]

I pay for a service. For $45/mo, they come out once a week and add "the required chemicals" including chlorine gas to the pool. In my limited experience, the price seems fair as long as they are doing their job.

 

[Uncle Flappy]

Test kit has been ordered and should be here by Friday. For what it is worth, below is a picture of the "organic material" taken underwater with a GoPro:

Sure looks like Algae to me.

- Flappy

 

[borjis]

definitely

 

[domct203]

Test kit has been ordered and should be here by Friday. For what it is worth, below is a picture of the "organic material" taken underwater with a GoPro:

Sure looks like Algae to me.

- Flappy

Looks like algae to me too, in all it's organic glory!

Dom

 

[Uncle Flappy]

After complaining to my pool service, they sent an "expert" over. He tried telling me that what I am seeing is the breakdown of plant material, "phosphates", not algae since it brushes away to the touch and isn't slimy. He poured Phosfree into the skimmer, told me to brush the sides well, and said the green should be better in a couple days.

I'm not convinced and await my test kit.

 

[domct203]

Ah, he used "should" for the outcome.......

He doesn't sound to confident in his diagnostic and treatment, and neither am I. Too bad you didn't ask him where this "plant material" may have come from.

Dom

 

[sbcpool]

Once you get going (the initial conversion can be trying) you'll find that maintaining your pool the TFP way will only cost about what you pay your pool service, except you will have water that is so clear you can see a quarter on the bottom of the deep end and tell if it's heads or tails, and turn on the pool lights at night without a halo. Once you get a handle on your pool it doesn't take much more than dumping in a few ounces of bleach every day or two. The key is having a good test kit. Get that ASAP.

 

[Uncle Flappy]

Ah, he used "should" for the outcome.......

He doesn't sound to confident in his diagnostic and treatment, and neither am I. Too bad you didn't ask him where this "plant material" may have come from.

Dom

We've had quite a bit of monsoon weather, complete with high winds and strong thundershowers. He blamed that. I saw him test the water but when I asked what the phosphate levels were, he explained his kit could not test for that. So yes, all theory and no irrefutable data. "Should" is the easy way out.

The key is having a good test kit. Get that ASAP.

Kit is on the way via Amazon and will be here tomorrow. I'll figure it out and post the results on Saturday.

Once you get a handle on your pool it doesn't take much more than dumping in a few ounces of bleach every day or two.

I use a pool service not because I am incapable. I use it because I am lazy. I also often travel for work. Can this method be used weekly as opposed to daily? And yes, I have been reading Pool School but it is a lot to soak in and probably won't stick until I put it into practice.

Thanks for your help.

- Flappy

 

[sbcpool]

I use a pool service not because I am incapable. I use it because I am lazy. I also often travel for work. Can this method be used weekly as opposed to daily?

If you get a SWG or liquid chlorine injection system it's certainly possible. It's not possible with manual chlorine additions. If you're going to manage your pool according to TPF principles, you probably can't have a pool service. You will be fighting them constantly and they will wreck your chemistry by using pucks and mystery chemicals.

 

[domct203]

We've had quite a bit of monsoon weather, complete with high winds and strong thundershowers. He blamed that......

Irrelevant. My pool is under two big trees, we've had our fair share of downpours/thunderstorms and I do not have "phosphates" or anything else green growing in my pool.

I use a pool service not because I am incapable. I use it because I am lazy. I also often travel for work. Can this method be used weekly as opposed to daily? And yes, I have been reading Pool School but it is a lot to soak in and probably won't stick until I put it into practice.

Thanks for your help.

- Flappy

I don't see how any pool can be properly maintained on a once a week basis unless there is some type of automatic (liquid) chlorine dispenser or a SWG. Hopefully someone else with more experience can elaborate here.

Dom

 

[Uncle Flappy]

Testing kit (K-2006) just arrived and below are the results. This was my first attempt so fingers crossed that I did it right:
FC 8.2
CC 12
CYA 100
PH 7.4

Based on the chart in Pool School, the stabilizer level is way too high and FC too low. I'll test again in the morning to see if I get similar results.

 

[domct203]

Testing kit (K-2006) just arrived and below are the results. This was my first attempt so fingers crossed that I did it right:
FC 8.2
CC 12
CYA 100
PH 7.4

Based on the chart in Pool School, the stabilizer level is way too high and FC too low. I'll test again in the morning to see if I get similar results.

Congrats on your first test.

You should also test for TA & CH.

the CYA test tops out at 100, you could be much higher. Be prepared to drain & refill. You can do an Extended Test to get a better idea of your true CYA level.

You are correct that your FC is too low. BTW it's fine to use the 10ml sample for a 0.5 resolution, it will save on reagents.

Your CC of 12ppm is a serious issue. Perhaps that is a typo for 1.2?

You should read up on SLAM and OCLT procedures, and do an OCLT to see if organics are throwing a party in there.

Be be sure to get post a complete set of numbers, and double check that CC level.

Dom

 

[Uncle Flappy]

Your CC of 12ppm is a serious issue. Perhaps that is a typo for 1.2?
Dom

Yes, a typo. Well, to be honest, bad math. Forgot the decimal.
Sure hope I don't have to drain and refill. I have a well and the electricity to run it ain't cheap.

I'll do another test tomorrow and post the results. I appreciate all the help!

- Flappy

 

[JoyfulNoise]

Hey Uncle Flappy,

You've got algae.

I'm in Tucson too (east side) and I got the same exact weather as you. Guess what - no algae whatsoever. The service guy's (Pima Chemical, am I right?) weather explanation is bunk or, as Dom said, "irrelevant". My neighbor who gets his service from Patio Pools gets the same bogus excuse every time his pool clouds up (which is about every 2 weeks like clock work) - they tell him the "monsoons are really bad" or "Tucson is experiencing a bad algae summer", etc, etc. He asks me all the time how bad my algae blooms are, and I tick him off every time when I tell him my water is crystal clear all the time.

I'm going to lay it out plain and simple - you need to fire the service guys and find a way to implement TFPC Method even with your work schedule. What ails your water is simple - too much stabilizer (I bet your CYA is way over 100ppm) and not enough FC to keep the algae at bay. If you can figure out how to spend 5 mins everyday tending to your pool and maybe 20mins worth of testing twice a week, you can do the TFPC Method. Once per week service just doesn't cut it. They come in, inject a giant load of chlorine into the water which raises the FC up very high. Then that FC probably dissipates in less than two days and you left with minimal and ineffective FC levels until they return again five days later. Your water is on the chlorine yo-yo - too much all at once and then not enough to be sanitary.

Take it from a fellow Tucsonan, you can do this and your pool will never look better!!

Good luck.

 

[Uncle Flappy]

...Pima Chemical, am I right?

Bingo! JouyfulNoise, good to hear from another Tucsonian (Bear Down!). I'm on the other side of town near Marana. From where do you obtain your chlorine? Looks like a SLAM is in order as I still have the green stuff and what appears to be dead algae on the floor.

Firing the pool boys is definitely on the list and my CYA levels have me concerned. Did another quick test this morning using the 0.5 resolution and used the addition of tap water to CYA test. I only looked at FC and CYA:
FC 8.5, CYA 110

Being out of town frequently, I am curious about SWGs and will be learning more about them. I have a slim chance of getting the wife to add chemicals when travelling for work and am often out of town 4-5 days at a time.

- Flappy