frustrating cloudy water - pulling my hair out

I have a frustrating greenish cloudy water problem. Sorry for the long post; but I'll give as much background information as I can in case any of it is relevant.

The pool hasn't been clear since it has been opened (over 3 weeks now).

I have a 13,500 gal fiberglass pool, Sta-Rite sand filter - model T-200BP-1.

I live in Wisconsin and have a mesh winter cover.

We had an unusually hot spell (> 90 degrees) in April, at least 3 weeks before the pool was opened...no suprise, when the pool was opened, it was thick with green algae. (Lesson learned - need to open earlier if this happens in the future).

When the pool was opened, I had the pool service company replace the sand in the sand filter (Lesson learned - this probably wasn't necessary for a 3 1/2 year old sand filter).

I spent over a week maintaining slightly higher than normal sanitizer using liquid shock, but mostly trying to clear up the algae with algaecide (poly 60)...I wasn't making any significant progress, and started reviewing this forum for tips. (Another lesson learned - need to attack the algae with chlorine first)

I switched to maintining very high sanitizer levels using liquid shock, and this seemed to have a good effect. It **seems** that the algae is killed, and I've since scrubed off the algae from all pool surfaces and vacuumed it out.

However, I was still left with slightly green, cloudy water. My next step was to use clarifier - I suspected that my new sand wasn't as efficient at removing particles as my old sand...This seemed to help somewhat, but I still couldn't see the bottom of the pool clearly.

My next step was to drain approx 1/3 of the pool and refill with (private well) water.

After a couple of days since the refill, still have the same cloudy water.

I am entertaining a suspicion that the pool service company possibly messed up my filter when they replaced the sand. However, there is no sand in the bottom of the pool, so I don't think there is a broken lateral.

I have been not backwashing the filter because I've read that too frequent backwashing of a filter can cause problems (channeling?), and my pressure hasn't been rising at all. The lack of pressure rise seems strange to me.

This morning, I reviewed the manual for the filter- it says to backwash daily when opening the pool until it is "sparkling clear"...I just backwashed this morning, and plan to backwash daily unless I get different advice from this forum.

Here are my test results from the PS233 testkit:
FC 12.5
CC 1
TC looks like slightly greater than 5 (the max of the readout)
pH 7.5
Alk 190 (was approx 120 before refill with my well water)
Cya 60

Any advice would be greatly appreciated. Thank you.

If the water still appears somewhat green, I don't think you have completely killed all the algae. I would suggest shocking your pool up to 15 and holding it there. The key to killing algae is to sustain high cl levels. Test at least 2-3 times a day (more than that won't hurt) and each time, add enough bleach to get back to 15. Run your pump 24/7. I don't think you need to backwash daily unless your pressure is up 8-10psi.

Matt,

There is a greater than 90% chance that chlorine will clear your pool. You simply haven't been using enough of it.

Using bleach, bring your Cl level up to 20 - 22 ppm and KEEP IT THERE until your pool clears. Run your pump 24/7 during this process. There is no need to backwash unless your filter pressure rises more than, say about 5 lbs.

That's it. Don't put anything else in your pool....you're probably wasting your time and your money

There's a few caveats to the above.

1. Your alk is a little high but I don't think high enough to contribute to the cloudy water.

2. You didn't post CH. Test it and if it's below 400, disregard it.

3. Possible copper in the water but I doubt it.

Go to the grocery store and get some bleach.....lots of it.....it may take 24 hours or it may take a few days but it'll work. Run your pump. Your filter is fine as long as it's not spewing sand.

Remember the words I put in caps....KEEP IT THERE.....Test and add back to 20ppm 3-4 times per day if you can. :)

Quote:

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Originally Posted by mattmcarroll

This morning, I reviewed the manual for the filter- it says to backwash daily when opening the pool until it is "sparkling clear"...I just backwashed this morning, and plan to backwash daily unless I get different advice from this forum.

Here are my test results from the PS233 testkit:
FC 12.5
CC 1
TC looks like slightly greater than 5 (the max of the readout)
pH 7.5
Alk 190 (was approx 120 before refill with my well water)
Cya 60

Any advice would be greatly appreciated. Thank you.

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Ok, first of all you are on the right track but not quite in the right race. You've caught on to most of our tricks for cleaning up a pool but not all of them.

First: check the Best Guess Table for CYA levels. You will see that with a CYA of 60, you should be keeping your FC at 20ppm until it clears. 12.5 is far too low to do the job.

Second: Your TC is 13.5. TC = FC + CC and if you see a difference between the FAS-DPD (powder) test in Ben's kit and the "quick" test he provides, go with the FAS-DPD measurement.

Third: You have a F/G pool so you can have a high T/A with no problem. i normally like 180 to be the max for non-concrete pools, but that's really a safety margin below 200ppm. For now, don't worry about it--you have bigger fish to fry. As long as Calcium is below 500ppm, it shouldn't be a problem (you didn't post calcium)

Fourth: Not sure why your pressure isn't rising in your sand filter. Are you sure the openers used proper filter sand? If not, it's cheap to replace and I STRONGLY suggest you do that. But there's a cheap trick you can use to raise back pressure and increase your filtering right now and it may help a lot. Poconos and I have, for a while now, been adding DE to our sand filters to increase filtering with excellent results. DE is fairly inexpensive--I get 10# for about $8 and am still on the first 5# of the box I bought last August. You add about a cup (through the skimmer), and wait 20 minutes and see how much your pressure rises. With most people you only want the pressure to go up 1# but you may want to boost it to where you think it should be. That should help enormously. The only catch is you have to do this every time you backwash. (Backwashing everyday won't hurt a properly maintained sand filter at all--if the waste water goes cloudy, it's doing some good).

Caveat: If you see the DE being blown back into your pool, then you MUST stop because something IS wrong with your filter and that has to be fixed. Either they used the wrong sand, damaged a lateral, or didn't use enough sand (When my pool went in, the idiots working for the installer were only going to put 150# of sand in a 200# sand filter--Luckily I caught it before they closed it up.). Too much DE should not be blown back through the return--it should cause pressure to rise so much you to need to backwash.

Fifth: You said "Liquid Shock". That's basically bleach, though it may be 10% or 12.5%. No problem there, but you should only be using that or bleach right now to chlorinate. To get from 12.5FC to 20FC you need 2 gallons of regular (5.25%) bleach or 6.5 quarts of Ultra bleach (6%). Check it 2x to 3x per day and add bleach to get keep it at 20ppm--don't let it drop.

Keep doing what you are doing in addition with daily brushing, 24/7 filtering and daily vacuuming to waste.

As I said, you are mostly where you need to be, but with a few things more. Keep us posted.

Thanks, everyone, for your time and advice.

My CH is 320 (forgot to post before)

I brought the FC to over 20 this morning, then just checked it again: it was 18.5 so I added some more bleach.

I'll keep it over twenty until it clears up. It seems to be getting better already.

Regarding the filter: I'll get in touch with the pool service company about the type and amount of sand.

I also think I'll try the supplemental DE, but this may have to wait until tomorrow.

One additional question: should I be using blue clarifier while this is clearing up?

Thanks again. I'll give an update tomorrow.

Don't use the clarifier, stick with chlorine only.

Janet

Yeah, when one of us moderators speaks, if another doesn't, it's because we have nothing to add.

A quick update: the pool is definitely getting clearer. At this rate, it seems like another 24 hours at >20 FC will do the trick.

Thanks again -Matt

Water is now crystal clear!

I'll now start working on gradually bringing my TA down, and keep an eye on my filter pressure.

Thanks again, everyone

Be careful if your using Iron or metal heavy well water to fill the pool. You may have staining that occurs if your metals drop out of solution. I would pretest your well water for metals and if necessary filter out the metals before they get into your pool water.

Matt,

Good work. :)

This thread could be required reading for everyone who posts to this forum with cloudy and/or green water.

The issue always seems more complex than it really is.....usually because folks don't understand that the methodology is very important.

The overwhelming answer to get good looking water is.....Chlorine. But it must be applied in an organized manner with frequent testing and diligence.

Reread your first post, Matt. You did well to stop throwing all those "magic bullets" at your pool.....your results probably would never have been very satisfactory........not 'til you decided to apply chlorine using the correct methods. :)

Edit: I originally responded to gwrace1's great suggestion on testing/filtering my well water, but see that there is a forum area ( Stains & Metal Matters: Iron, Copper, Silver & More) meant for this topic. I'll read up there. Thanks, gwrace1 for the tip.

Quote:

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Originally Posted by duraleigh

Matt,

Good work. :)

This thread could be required reading for everyone who posts to this forum with cloudy and/or green water.

The issue always seems more complex than it really is.....usually because folks don't understand that the methodology is very important.

The overwhelming answer to get good looking water is.....Chlorine. But it must be applied in an organized manner with frequent testing and diligence.

Reread your first post, Matt. You did well to stop throwing all those "magic bullets" at your pool.....your results probably would never have been very satisfactory........not 'til you decided to apply chlorine using the correct methods. :)

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After posting about our gradual recovery from algae, haze & chemicals, I'm fine-tuning based on the tips here! If I'd caught this thread, I wouldn't have needed to post :o Thanks to all & Congrats Matt.

OK, now I see... my water too is cloudy, a light greenish cloudy but the green is coming from the "blue shock" stuff.
I have an above ground 24x24, if I remember correctly its around 13,000 gallons of H20. Should I get my FC (free chlorine?) up to 20 also? Just keep adding the bleach until I get to 20 (if thats the reply that I get) until the H20 gets clear?
Thanks in advance!!
Kim

Yes to cl level at 20 until it clears. I don't know what "blue shock" stuff is, but just stick with bleach. It won't cause cloudy water problems. Run the pump 24/7 also.

thanks WaterMom, we leave our pump running 24-7 all the time, don't most people? What would the purpose be for not running it?
Thanks so much, I am bringing home bleach TOMORROW!!!

You really only need to run your pump approximately 10 or so hours per day. But, when you are trying to clear it, you need to run it 24/7. Keep us posted how things are going.

WOW! I never knew that!! Everyone I know runs theirs 24-7!!
I will and thanks!