Help Recovering Pool's Chemistry

[LivingWater]

Hi everyone,

I am completely new both to pool maintenance and the forum. I have undertaken the responsibility to recover and maintain my boss's 30,000 gallon vinyl above ground pool, and I need help with some pool chemistry.

I came to the pool 3 weeks ago, and it was a dark green lake. It had been neglected of ANY maintenance for 2 years. I found what I could on this forum to get going on killing the algae. I used a lot of the bagged shock, containing trichlor, along with a lot of bleach and granular chlorine. After 4 or 5 days, the water turned murky blue. Adding a lot of Chlorox Clarifier, the water progressed to where I could faintly see the floor of the pool. I have spent the last several days getting the last bit of leaves out of the bottom, scrubbing the vinyl, and adding chlorine to keep the algae away. Now, the water is very blue but also very cloudy again. I believe the cloudiness is due to the white/gray-colored algae particles still floating around and also settled on the pool floor. Not sure though.

I finally was able to use my new TF-100 test kit to check my levels yesterday. Here is what I found:

FC: 0 (possibly "chlorine lock" from what I've read on the forum)
CC: No time to check
pH: maybe 5.0 - 6.0? (too low to compare to the color readout)
TA: Confused... (Upon adding the 5 drops of R-0008, water immediately turned the pink color that it SHOULD turn after the R-0009 is added, instead of turning green first)
CH: No time to check
CYA: 100-110

Based on my limited knowledge of pool chemistry and how to adjust these measurements, it does make sense to me that my excessive addition of the trichlor shock contributed to my high CYA reading, which may in turn be giving me my FC-0 reading as well. Please offer me all the help you can regarding all the necessary steps I should take to removing ALL of the dead algae and correcting my chemistry.

Thank you!

 

[jblizzle]

Welcome to TFP!!!

"chlorine lock" is a myth and I certainly hope you did not find otherwise on this forum.
You need to check the CC (how did you not have the 10 seconds to test it? )
pH and TA have crashed VERY low because of all the dichlor and trichlor you were using.
CYA is now WAY too high also because of all the dichlor and trichlor you were using.

At this point due to the high CYA, you need to drain and replace at least 50% of the water.
In addition, the low pH could very well be fading the liner.

So, step 1: start adding borax to get the pH back into the 7s (use PoolMath).
step 2: Replace a lot of water
step 3: post up a full set of test results.

You also need to slow down and do some more reading I think. Start with these:
ABCs of Water Chemistry
Recommended Pool Chemicals
How to Chlorinate Your Pool

I hope you have a good relationship with your boss

 

[Richard320]

Welcome!

Now for the unpleasant news. Trichlor is very acidic. That is why you have super low TA and super low pH.
The low FC is because you still have algae. With the high CYA you now have, it certainly isn't due to sunlight UV degradation.

What come next is a partial drain, to get CYA down to some reasonable number. Take advantage of the low water level to get in there and remove any ladders and steps and scrub them out while access is easy. Do not drain the whole pool, lest the vinyl liner shift and create even more mess. After you refill, you see where you're at and adjust pH and TA. And then, finally, you proceed with the Shock Level And Maintain Process.

It's a pity you didn't find this site earlier. You could have been one of these success stories. Read 'em if you want; I'd suggest just scrolling through and looking at the pictures.

http://www.troublefreepool.com/threads/79787-Gone-for-2-months-and-return-to-a-swamp
http://www.troublefreepool.com/threads/74959-How-much-chlorine-will-I-need-(gross-numbers)
http://www.troublefreepool.com/threads/75213-the-pool-is-winning
http://www.troublefreepool.com/threads/72594-Proud-owner-of-a-glorious-swamp
http://www.troublefreepool.com/threads/46472-Frog-Filled-Green-Swamp-to-Oasis-Work-in-Progress!!!

 

[LivingWater]

Thanks for the help!

I just drained about 75% of the pool, and am ready to vacuum the remaining visible 'gray' particle algae still settled on the floor of the pool before refilling and balancing my chemistry levels. I have ready several of the 'losing prime while vacuuming' threads on the forum, but I haven't seen anyone trying to vacuum the pool floor while the pool level is well below the skimmer (i.e. only water into the skimmer/pump is from the vacuum hose). Is this possible to maintain a good prime on the vacuum if I only have about 10inches of water in the pool? I'd like to vacuum the floor while the water level is at its lowest for best visibility.

Thanks for any help you can offer.

 

[timerguy]

Are you saying the shallow end is dry?? I doubt the vacuum will work without water in the skimmers. You should never leave less than a foot of water in the shallow end of a vinyl pool. When I was draining and refilling my 24000 gal pool that meant I could only do 8000 gals at a time.

 

[danacc]

I don't know about vacuuming when the skimmers are dry.

Go ahead and refill and retest the water. Get it balanced, and then worry about vacuuming.

 

[LivingWater]

I decided to go do as danacc suggested in refilling, retesting, and balancing the water. These are my test results as of this morning:

FC: 7.5 (Goal: 10 - shock level per CYA level)
pH: 6.8 (Goal: 7.7)
TA: 40 (Goal: 100)
CH: 150 (Goal: 250)
CYA: 20 (Goal: 40)

Things are looking UP!!! Water is crystal clear now with my chemistry levels on the increase toward my goals during the SLAM process. Still having issues keeping prime on the vacuum hooked up to the skimmer. The sediments on the floor of the pool are incredibly fine particles (light brown/whitish in color) that are very easily disturbed. Should I be vacuuming on the 'PUMP TO WASTE' setting or 'FILTER TO WASTE' setting for best results? It seems that I'm getting more powerful suction on the vacuum with 'PUMP TO WASTE' than having it go through the sand filter, but it has been hard to troubleshoot exactly what my issue is. I keep losing prime after about 20 to 30 seconds it seems. Not sure if those sediments are clogging up something in my pump filter or my sand filter or what... Please give any advice on getting these last spots of fine sediment off the floor of this pool. Greatly appreciate all the help.

 

[CUTiger78]

LW, I've got one question for you - Are you sure it's 30,000 gallons? That's a mighty big above ground pool.

Just askin', since it'll really affect the amount of chemicals you have to use.

Good luck!

 

[jblizzle]

Why are you raising the pH and TA so high?
Why are you adding CH to a vinyl pool?

 

[LivingWater]

Actually, thank you for mentioning that. I forgot to change it on my signature. It appears to actually be about a 20,000 gallon pool. 30,000 was my estimation when I first took on the job (its my boss's pool).

I have been adding chemicals according to the correct volume, just forgot to update my signature... thanks for the heads up.

- - - Updated - - -

Why are you raising the pH and TA so high?
Why are you adding CH to a vinyl pool?

For the pH and TA, I have seen 7.7pH and a TA of 100 as being toward the high end of both ranges. I thought I might should shoot for a little higher than middle ground in order to help keep the algae away at the beginning. Then, I could let them drift down a tad...?? Am I off in thinking this way?

 

[jblizzle]

pH and TA have nothing to do with algae. You could bump the TA a little, but I would keep it around 70ppm.
Algae is kept at bay by maintaining adequate FC levels which is a function of your CYA level.
You want the pH to be around 7.2 before you start the SLAM process as well.

Please review the links I provided to you back on the 31st ... specifically the ABCs article.

 

[LivingWater]

Thank you, jblizzle, for clarification on the pH and TA relationship to algae. After a few days worth of adding the recommended doses of chemicals per PoolMath, here are my results:

FC: 3 (Overnight loss of 1ppm)
pH: 7.5
TA: 110 (somehow got a little high... not sure how?)
CH: 150
CYA: 20

This is with very clear water, although I still need to vacuum out some sediment in the pool floor. My levels seems to have balanced out pretty well. Should I up my CYA level just a tad in order to ensure my chlorine is getting enough protection from the sun to do its job? I get quite a bit of direct sunlight, using 6% bleach from a Dollar Store in town. Doesn't seem like my bleach is doing quite what PoolMath says it will in increasing my FC with each addition. (Ex: I went for shock level last week from 2FC to 10FC, added a little more than the recommended chlorine amount, still came out to only 7.5FC on my next reading) Not sure if this is due to my lower CYA or not... Any help in fine tuning is appreciated. thanks.

 

[timerguy]

Avoid Dollar stores !!!!! Their stock can be very old and many do not have a % on the label! A tad for you would be 50 with all that sunlight. Don't worry about the TA, your fill water may be that high! When was your next reading? A day later could easily see a drop of 2.5 or 3 or maybe even 4. Yes, your low cya could definitely cause a higher daily drop.

 

[LivingWater]

Ok, great. I haven't found a good thread explaining the best way to add CYA to achieve the desired level. How should I go about doing this? There is a hardware store that does care the Stabilizer (I believe in granular form??). Should I be able to trust PoolMath on the quantity of stabilizer to add to bring mine from 20CYA to 50? Should I sneak up on it, and if so, how?

Exactly what timerguy said above, I have seen about an average of a 1.5 to 2.0 FC drop day to day so I have been adding more chlorine than I would like on a daily basis. Just as a rough reference, with good quality bleach, about how often should I be needing to check my FC level to determine the amount of bleach to add? I have the TF-100 test kit, and I have been check my FC level almost every day for a couple weeks. At what point (again, when using good quality bleach and less than 1ppm loss overnight) can I space out my testings in order to make my reagent quantities last an optimal length of time?

Appreciate all the advice. Again, I'm new at this method of pool maintenance, but it sure does work!

 

[jblizzle]

Recommended Pool Chemicals explains how to add chemicals. For CYA, you put it in a sock and either tie it in front of a return jet or set it in the skimmer. Squeezing it will speed up the process.

Yes, trust PoolMath. You may want to just target 40ppm and then test in a week to see where you are and add more if you desire.

If you are only having to add 1.5-2ppm of FC per day, that it about as good as anyone can hope for.

 

[timerguy]

Shopping around for the best price for 100% cya. I get mine in 6.5lb bottles at Walmart for < $20. Google pool Stabilizer mine is mysaltpool http://www.walmart.com/msharbor/ip/My-Salt-Pool-Saltwater-Stabilizer-6.5-lb/34752155 Kmart or home Depot may carry it too. Put it in an old athletic sock (hole-less) in a skimmer or in front of a return jet will work. Squeeze it occasionally to speed up the dissolve process. Yes, trust pool math to determine how much, then sneak up on it (40 to start then 50 once you have a good test) It may take as much as a week for it to show up on your test. But assume it's there. FC test and bleach additions daily until you can accurately determine your daily loss which you can test using the OTO. I use the FAS-DPD daily.

 

[LivingWater]

Ok, about 10 days ago I purchased enough granular Stabilizer (CYA) from Walmart to raise my level from 20 to 40. I added the stabilizer to the skimmer with the pump on recirculate. I let the circulation go for about a week and rechecked my CYA level, but now I am showing near 0 on my reading!?!

All I have done in the meantime was add some bleach daily to maintain my FC level but nothing else. How in the world would I see a DROP in my CYA level after adding that much to my pool? I am rather perplexed by this one. Any help?

P.S. I have left my TF-100 TestKit out in my truck during our hot Texas summer heat a couple of times by accident. Could heat have a grave effect on the R0013 reagent used to test my CYA, giving me a false reading of 0? My other reagents seem to be giving me reasonable level readings so I didn't think this was the case, but thought I'd throw the info in there in case someone knows something I don't!

 

[jblizzle]

So you dumped the granules into the skimmer on recirculate? Did you see then come shooting out of the jets then? Is it all sitting on the bottom of the pool?

What kind of FC and CC readings do you get?

Different lighting for the CYA test?

 

[pwrstrk]

Going forward for your CYA additions put the CYA in a sock and hang it in front of a return with the pump running until it's dissolved or in the skimmer basket with the pump running until it's dissolved. Don't just pour it in the skimmer. Not a good practice.
Also make sure you store your test kit in a cool dark place. Your reagents will last the longest that way. ?