Indoor SWCG Pool, cloudy/ green

[waste]

Hi all, I don't often need to ask ?s here, but this has me stumped.

I've recently had to work on an indoor pool (13,500 gal, liner, spillover spa) that went 'cloudy' on us. I had the 'AquaTrol' dialed down to producing 30 min/day (I've had other indoor units that were over-producing cl, so I started this on low - expecting no other problem than too much cl). When it got cloudy, I shocked with 1/2 gal 12.5% chlorine, the water cleared up. A week later, my boss went out to see the pool and it was cloudy again and showed NO cl reading on the test strip. He added 1/2 gal of 12.5%, and told them to add the other 1/2 gal the next day (he also bumped the dial on the SWCG to 20) When I went yesterday, the water had taken on a definate GREEN hue and there was a feelable 'film' on the walls. The reason I went out there wasn't for the 'green', but because one of the contractors had somehow put some iron bits into the pool, which are starting to rust (I will bring some ascorbic acid when I go back on Mon.)
My problem is that the owner 'topped off' the pool before I got there, with well water. I don't carry a metal test kit with me when I go out.
As the last peice of info, we had to put a solar cover (blue bubble) to keep evaporation down (the dehumidifier that was installed isn't working properly). I don't know if I messed something up or the well water messed things up ( I added 3# cya 2 weeks ago), also I saw LEAVES! in the pool. In short, I don't know what's happening, and would appreciate ANY help.

[chem geek]

My only guess is that you've got an algae bloom started and it is consuming the chlorine. I don't think that metals would consume chlorine so I would assume that the cloudy and then green are due to algae. I'm not sure why the SWG isn't handling the situation, but maybe it's not working for some reason. When it's turned on, you should be able to take a sample of water coming from the return and measure higher chlorine levels than found in the rest of the pool. If not, then the SWG isn't producing chlorine for some reason.

That's my best guess at this point. In any event, you'll have to get chlorine into the pool, manually (chlorinating liquid) if necessary and keep adding it until the chlorine demand is gone which would mean the algae was gone. You might try checking the filter since perhaps there is algae there as well and would need to be cleaned out.

Richard

[aquarium]

( I added 3# cya 2 weeks ago)

Why would you add CYA to an indoor pool?

[waterbear]

Why would you add CYA to an indoor pool?

My question too! If you could post a complete set of results it would be helpful. The fact that it went cloudy and then cleared kinda indicates algae or organics in the water. The leaves are a puzzle but that tells me that someone is letting stuff get into the pool that shouldn't!
How many hours pump run time and what percentage on the Aquatrol and what is the salt level and temp of the water?
Well water might or might not be a problem. Test the fill water and post the results.
Green water and iron bits in the pool? Perhaps blue vinyl liner and yellow water from the iron is causing the green color since it appeared after the clorine output on the generator was bumped up.
Don't think the cover would have much impact, short of preventing some outgassing, in an indoor pool.

[waste]

Hey guys, thanks for answering!

I went out this AM to see the pool again, but couldn't get in (I had talked to both husband and wife and they assured me that the door would be left open if no one was going to be home - it wasn't) So I can't give the chem #s from today - and I don't know if there's still a problem.

It's been asked by 2/3 of the respoders 'why I added cya to the pool?' I was remembering this

I personnally am considering recommending that a small amount of CYA (around 10-20 ppm) be used in indoor pools to reduce the chlorine concentration which not only should make swimsuits last longer and the air smell less like chlorine, but should also reduce the disinfection by-products (DBPs) that are produced.

from http://www.poolforum.com/pf2/showthread.php?t=6364 #6 by Richard (as I said, I was worried about too much cl being produced, as has been my experience with indoor SWCG pools) (& though I couldn't find the thread, I thought it might prevent some oxidation of the metal rails, etc. in the pool - esp the light screws, which was a problem all last year in our SWCG pools) I figured it wouldn't hurt to have ~20 ppm in the pool, and could prevent some problems that might arise (I know, with 3# the cya should be ~30ppm- I told my partener too add 1/2 of the 4# container, but he figured 'if some is good, more is better' )

If I get out there again, I'll get the full set of #s (I couldn't last time because my partener had let my test kit FREEZE !!!- I'm not sure if the reagents are still good, but I've still got my 2005k)

Tom, did you ever figure out what was going on with your Polaris 180?

Evan, I've tried to look into the deck jets, but don't have access to the office, I talked to someone at our distributer - but he was clueless - sorry!

Again, THANKS!!! for the responses!! - Ted

[waterbear]

Evan, I've tried to look into the deck jets, but don't have access to the office, I talked to someone at our distributer - but he was clueless - sorry!

Thanks for trying! I appreciate that. I finally got the correct jet nozzles. One of our distributors recently got a new employee who was formerly a Zodiac rep (They own Polaris) and she knew EXACTLY what I wanted and even knew the correct part number! I got them three weeks after ordering (they needed to be special ordered)! As soon as the pool is warm enough to get into I am going to install them.

[aquarium]

Tom, did you ever figure out what was going on with your Polaris 180?

It seems to have resolved itself.

I think it just might be reacting to our sudden temperature changes.

[chem geek]

When CYA is added to a pool, a higher FC level is needed to prevent algae (but you already knew that). Though you were worried about too high a chlorine level, it would appear that in this pool there is too little chlorine generation to maintain a high enough FC, especially for the CYA level, though I don't know why. Perhaps there was even more CYA added than you think -- a full set of measurements would be helpful. If the FC was very low to begin with, then adding CYA would have made the disinfecting chlorine level too low so algae could develop.

Also, if you use CYA in the indoor pool I had also mentioned that the use of non-chlorine shock might be required since achieving breakpoint with chlorine alone is always difficult in an indoor pool (due to lack of sunlight) and that with CYA it's even harder. If you add chlorine and find that the FC eventually gets stable (doesn't get consumed) but that the CC level is high and doesn't go down, then the use of non-chlorine shock (KMPS) would probably be needed to shock and as ongoing maintenance, though in theory the SWG should be able to shock the pool even with CYA in it.

I'm still betting that the SWG stopped working or was set too low. Either that or the amount of CYA that was added was a lot more than you thought.

Richard

[waste]

Richard, again I thank you for your input!

When I was first called out there for the 'cloudy' water, others had been there and added the salt (however, they neglected to turn the SWCG 'on' ) I added 12.5% to compensate and turned the d*mned thing on. (Part of the problem is that I'm only getting 'called in' when something goes wrong). It went from 'cloudy' (~white~ precipitation) to clear after I shocked it, then back to the same 'cloudy'. My boss called me (I should charge him for the call ) and added more 12.5% after talking to me and 'upped' the output on the cell (was at 5% and he turned it up to 20% -after I told him how to do it )
The water went (over the course of 5 visits, 2 of them I was there to supervise) from cloudy to clear, back to cloudy and then to the 'green' (water not cloudy, but 2 days later- when I got there to 'clear', but with a green hue to the water)

I'm almost sorry I created this thread, as I'm the only one ( in my company, the owner included) who cares (or has taken the time, to try and figure out what's going on), however - I guess that's the price I have to pay for making enough $ to afford new furniture (that's why I gave my test kit to my partener - I had to stay home to receive tne new living room set, so I (foolishly) entrusted him w/ my kit).

I strongly suspected that algae had entered the pool, but was wondering if, with the solar cover on, the chlorine (5+ ppm) couldn't do it's job, without being able to 'outgas'

I don't know how 'outgassing' effects a pools' ability to 'clear-up', which is why I turned to you and Evan -- I'm meerly a questor here, trying to make sence of 'what's going on'

Richard, as always, thank you for the info you share!! -Ted

[chem geek]

I have an opaque pool cover, maintain chlorine levels, use CYA (around 20 ppm) and never get algae. Yes, it's an outdoor pool, but even when it's covered for days or a week at a time nothing goes wrong with it. Now that doesn't prove anything since it's just one data point, but your use of a pool cover may have caused the pool temperature to rise and that is something that the algae may have liked -- so if the pool was on the "edge" of developing algae, that could have pushed it over.

You said there was 5 ppm FC, but when you measured later when it was green there was no FC at all so I'm still betting that the FC didn't hold, though again I don't know why (if the SWG was working). This sounds like a classic algae bloom that must be fought with frequent additions of chlorine until the chlorine holds after the water clears, but usually with an SWG you can just run it more frequently (even continually) and the high chlorine in the cell will blast most of the algae. So something here still doesn't add up. Have you measured the CYA level yet?

I doubt that simply being an indoor pool with CYA is the culprit, but if it is then I'll have real egg on my face. I knew that achieving breakpoint (keeping CC low) is hard in an indoor pool and that CYA makes that harder, but did not expect algae to develop -- it just doesn't make much sense.

Richard