1 month with clody water

Algae problems in swimming pool water.
Green (cloudy) water or slimy pool walls.
Black algae. Mustard algae. Pink or white pool mold.
Guest

1 month with clody water

Postby Guest » Wed 26 Sep, 2007 18:07

I've been coming here for a little while trying to find the answer to my problem. Today I've received my test TF-100 and i will post my reading below. Well...my pool has been cloudy for the past month with a lot of algae. I use power powder plus which is calcium hypo... and I can't seem to get my water clear, plus 3" stabilizer tablets which I've removed a couple of days ago, no matter what I do to the pool the water is very hazy, i only use the power plus as chlorine since the pool guy told me this was better than liquid chlorine. I run the pump for 8 hours a day to no avail...here are my readings
FC=11
CC=0
TC=0
PH=7.5
T/A=80
CH=440
CYA=60

Please help, summer is almost gone and my kids are dying to use the pool but it looks very sad


chem geek
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1 month with clody water

Postby chem geek » Wed 26 Sep, 2007 19:32

You are correct to stop using the stabilizer tabs/pucks as your pool already has 60 ppm Cyanuric Acid (CYA). For every 1 ppm FC added by Trichlor pucks, it also adds 0.6 ppm to CYA. Higher CYA levels make chlorine less effective.

As for Cal-Hypo, I would stop using that as well since your pool already has 440 ppm Calcium Hardness (CH). For every 1 ppm FC added by Cal-Hypo, it also adds 0.7 ppm to CH. Your water is already currently saturated with calcium carbonate so adding any more Cal-Hypo or having the pH go up would make the water even more cloudy, though I suspect the cloudiness is algae trying to bloom. Your pool guy is absolutely wrong about Cal-Hypo being "better" than liquid chlorine. They are identical in the water, both producing hypochlorous acid, but the Cal-Hypo also adds calcium which does NOT make it better. The only thing better about Cal-Hypo is that it is denser in chlorine so it's less weight to carry from the pool store to your pool (the same is true for other sources of chlorine -- Trichlor being the "most concentrated chlorine" in that sense).

There are several things you need to do. First, you should be filtering 24/7 until this gets cleared up. Second, check to make sure your filter isn't really dirty and clean it (backwash if sand, etc.) if it is. Third, did you shock with chlorine? Though 11 ppm FC at 60 ppm CYA is fine for keeping away algae, it isn't enough to kill a developing or full-fledged algae bloom. Do you find that the FC level drops at all overnight (it obviously drops during the day due to sunlight)? If so, then you've most certainly got a nascent algae bloom. You need to shock the pool with liquid chlorine -- unscented bleach or chlorinating liquid -- at a level of 24 ppm FC and hold it there, but before you add the chlorine, first add some Muriatic Acid to get the pH down to 7.2 first. Fourth, you need to brush the pool regularly, both for thorough mixing of the chlorine and to scrape off any algae formed on pool surfaces.

You didn't say the volume of your pool so I'm going to give you quantities that apply to 10,000 gallons and you can scale accordingly. It will take 13 fluid ounces of Muriatic Acid (added VERY slowly over a return flow at the deep end with the pump running) to lower the pH from 7.5 to 7.2. It would take 34 cups (2.1 gallons) of 6% unscented bleach or 17 cups (just over 1 gallon) of 12.5% chlorinating liquid to add 13 ppm FC to your pool to get to 24 ppm -- and then you'll need more as this gets used up killing the algae. When adding the chlorine, do so by pouring very slowly over a return flow at the deep end with the pump running. If you do not have a floor drain, brush the sides and floor in the area where you add the chlorine to thoroughly mix it (same is true for the acid addition).

You need to maintain the 24 ppm FC level until the following three things all occur: 1) the pool becomes crystal clear, 2) you measure minimal (<= 1 ppm) FC drop overnight and 3) you measure minimal (<= 0.5 ppm) Combined Chlorine (CC).

Since your pool is only at the cloudy stage and not a full-blown green algae bloom, it should only take a couple of days to clear this up, maybe 3. Basically, it takes about as long to clear a bloom as it takes to develop -- they don't start out instantly as algae only doubles in population every 3-8 hours. So water starts out just looking "dull", then slightly cloudy, then cloudy, and then green when enough algae clump together to clearly show color (instead of just diffusing light which makes water look cloudy). Clearing a full-fledged algae bloom (upon spring opening, in this case) is shown at this link that took about 4 days to clear.

Richard
Guest

1 month with clody water

Postby Guest » Wed 26 Sep, 2007 19:40

thank you Richard, i will follow your advise, by the way my pool is about 17000 gallons
chem geek
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Joined: Thu 21 Jun, 2007 21:27
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1 month with clody water

Postby chem geek » Wed 26 Sep, 2007 19:46

So just multiply my quantities by 1.7 and you should be fine.

One other thing that is possible is that if your pool doesn't have a floor drain, then even killing the algae may not clear the pool if the cloudiness tends to just settle to the middle and bottom of the pool. Though chlorine will eventually oxidize all the algae, that takes a long time so filtering with cleaning/backwashing is better, but if the circulation is poor because of no floor drain (e.g. an above-ground pool), then it is sometimes better to use a flocculant, OMNI Liquid Floc Plus (which is done with the pump off) and then vacuum to waste that which consolidates to the bottom. You're not that this stage yet, but I just wanted to give you advance warning if you get to a point where the algae is all dead, but the pool still isn't clearing.

By the way, after you add the acid to get to 7.2 in pH, see if the water looks any clearer. If it does, then at least some of the cloudiness is from the Cal-Hypo you've been adding, making the water saturated with calcium carbonate. Also, the pH test won't be very accurate when you get to very high FC well above 10 ppm, but don't worry about that. If you initially get to 7.2 and then add more chlorine, you should be fine even when you let the chlorine come back down after you're all done and can then adjust final pH...but we're not there yet.

Richard
Guest

1 month with cloudy water

Postby Guest » Wed 26 Sep, 2007 19:49

another question, once I reach the 24 FC, do I keep the PH at 7.2?
Guest

1 month with cloudy water

Postby Guest » Wed 26 Sep, 2007 19:52

as for stuff sitting at the bottom, I have a navigator running all over the floor and the walls
chem geek
Pool Industry Leader
Pool Industry Leader
Posts: 2382
Joined: Thu 21 Jun, 2007 21:27
Location: San Rafael, California

1 month with cloudy water

Postby chem geek » Wed 26 Sep, 2007 20:04

Don't worry about the pH when the FC is at 24 ppm. The pH will rise when you add more chlorine which is why I'm having you lower it somewhat in advance. The chlorine will still be reasonably effective as CYA acts as a chlorine (hypochlorous acid) buffer so resists changes in chlorine concentration with changes in pH (which is a good thing). When the chlorine gets used up, the pH will drop back down (that's something people don't usually tell you and instead claim that liquid chlorine is high in pH when really using it on a regular basis is pH neutral since the usage of the chlorine is acidic and exactly compensates for the initial rise in pH upon addition -- so the pH will go up when you raise the FC, but will come back down when you eventually let the FC drop down).

I'm not sure if your Navigator cleans as well as your filter. If it does, then you should find it gets dirty with your cloudy pool. If not, then perhaps your algae isn't clumped and isn't that far along so either 1) the higher chlorine will clear it (i.e. it won't be too much to oxidize reasonably quickly) or 2) we can use the flocculant which will give your Navigator a lot to clean! Let's see what happens with the shock levels of chlorine first.

Richard
Guest

1 month with cloudy water

Postby Guest » Thu 27 Sep, 2007 06:30

Richard, thank you for your valuable information, I will be visiting Lowes today and buying a truckload of bleach. What do you use to rise the alkalinity and PH besides that expense Leslies powders?
pool doctor

1 month with cloudy water

Postby pool doctor » Thu 27 Sep, 2007 09:27

have you tried floc yet? I swear by the stuff and so do all my customers
Guest

1 month with cloudy water

Postby Guest » Thu 27 Sep, 2007 11:47

pool doctor wrote:have you tried floc yet? I swear by the stuff and so do all my customers


No, not yet, the thing is that is been raining here in south Fla for 4 days straight and is tough to go out back in the middle of a thunderstorm so I'm waiting for tomorrow since is going to be nice, to start the whole process. Where do I get floc?

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