Causes and cures for cloudy swimming pool water.
Milky pool water, white, pink, brown, purple, black cloudy water.

Well water in pool

Postby debfrost » Mon 21 May, 2007 23:29

I just wanted to let you know that if all of your levels are "perfect", but your pool water is discolored and cloudy, you may have iron or copper in your water and no amount of shocking or flocking will help until you get a metal agent in your pool. Make sure that you dont put any chlorine in before or after(depending on the instructions)
This has been a great problem with our well water.

Hope this helps

Pool Slave

well water

Postby Pool Slave » Fri 01 Jun, 2007 13:41

I also used well water to fill my pool. I have a 27 x 4 above ground. I have very hard and rusty water. I knew that this would be a problem with my water chemistry so I thought that I would try to filter my water as I filled my pool. I piped 3 whole house filters together in series with a 20 micron filter in one, a 5 in the middle and a 2 micron in the last filter and I have not had any of the problems that all my "expert" friends said that I would have. I also did not spend the $800 that it would of cost to truck in water to my pool either.

Great forum, many good ideas and a few laughs thrown in to. :lol:


well water

Postby wejj » Sat 02 Jun, 2007 22:19

I also, use well water with high rust and iron to fill pool. Natural Chemisty makes a great product for removing metals from pool. It is called METAL FREE. I pour it into the pool before shocking so the chlorine does not react with the metals. I brush the pool and Metal Free deactivates any rust that was sitting on the bottom.

Good Luck to you


Postby MICHIGAN » Tue 05 Jun, 2007 10:48

I have a 18 ft round 4 ft deep pool. I lost the cover in the pool over the winter and the pool was very green when I opened it. I shocked and put algi-crush to kill the algea and it turned a blue color but I couldn't see the bottom. I then flocked the pool, waited 4 days and I could see the bottom but it had a white cloud on the bottom. When I begain sweeping the water got cloudy again. I have a cartridge not a sand filter so I decided to let it settle again it takes about 8-10 hrs to settle and I resweep same thing happens. Should I floc again or what else can I do to get the water clear even after I sweep.The water isn't completly clear when it settles but at least I can see the bottom until I run the filter or sweep.

Postby samantha » Mon 29 Oct, 2007 20:32

my pool is cloudy all of my levels are normal. i have flocked and a million other things. ive backwashed with no luck. my husband turned the pool off for a day and it completly cleared up but as soon as he turned it back on you could not see the bottom again. sand filter 18x33oval above ground pool. going on three months trying to fix cloudy water.

Postby samantha » Mon 29 Oct, 2007 20:34

oh yeah also i use phosfree to keep out algea
chem geek
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Postby chem geek » Mon 29 Oct, 2007 22:20

Cloudiness is usually due to one of three things:

1) an impending algae bloom since it looks dull, then cloudy, before it turns green

2) over-saturation of calcium carbonate which can also lead to scaling

3) poor filtration so too many suspended solids in the water

Since you are using PhosFree, it's probably not #1 (algae). Since the problem only occurs during circulation, it's probably not #2 and most likely to be #3 which means that your filter is not catching suspended solids in the water. When the pump is turned off, they settle more to the bottom of the pool. However, if you used a flocculant, then you should have had sediment at the bottom that you could vacuum up. If you did that and it did not work, then perhaps it is #2.

If you test your water and post the water chemistry parameters, then we can see if that's the problem. If the pH, Total Alkalinity (TA) or Calcium Hardness (CH) are high, then the water could be over-saturated with calcium carbonate. If the water chemistry turns out to be OK, you should check your filter -- perhaps its cartridge needs to be cleaned or replaced (or sand backwashed, etc.).


Cloudy blue water after Flocking and Pump on 45 min Cycle

Postby Wetwillie » Sat 19 Apr, 2008 20:11

I keep reading RUN your pump for a couple of hours after flocking then turn it off! I can't run my pump for an hour before I have to backwash it. I have had my pool for 15 years and this has never happened. So I replaced all the filter grids (DE filter) and it still needs to be backwahed every 45 minutes or so. I replaced my presure gage too - figuring that it might be bad but it wasn't. I'm on my 4th 24lb bag of DE... this can't be right.. anyone...???
Pool World Guy

your pool

Postby Pool World Guy » Tue 13 May, 2008 15:41

First don't put liquid chlorine in your pool please its not good for it and can cause cloudyness not to mention give you terrible issues with your cartridge filter.

second to the guy who says he prefers cartridge filters sure they will do the job but your micron filtration level will never be as good as it would with a sand filter and even better with a DE filter your water your cleanliness level. p.s. there is more to cleaning yor filter than just rinsing it I hope your local pool store can help you with this.

Ok as for your levels drain half your water and refill it most wells have Iron in the water and is why you get that rust color or copper but its usually iron . Adding liquid chlorine will not help only complicate things i know its cheaper to try and cut corners and there is a type you can use but ost grocery stores dont have the proper kind. you will need something to get rid of your metals there are flocculants that work for this go to a pool store and ask not a place like walmart where you probably got your intex pool they dont know anything and will just say whatever to get you out of their face. also flocculants work but only for 24 hours if i doesnt settle out start up your system again and get the water circualting for 24 hrs and then add new flocculant and turn off everything let it settle and vacc it out.

Hope this answers some questions
chem geek
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Re: your pool

Postby chem geek » Tue 13 May, 2008 20:43

Pool World Guy wrote:First don't put liquid chlorine in your pool please its not good for it and can cause cloudyness not to mention give you terrible issues with your cartridge filter.

Needless to say I disagree. No one is saying to pour liquid chlorine into the skimmer. If you add it as you should with almost all chemicals very slowly over a return flow in the deep end with the pump running, then there is no problem and the chlorine added from ANY source is identical in the water. The only differences in chlorine are whatever else gets added to the water (and the initial effect on pH). With Trichlor, for every 10 ppm in Free Chlorine (FC) it adds, it also increases Cyanuric Acid (CYA) by 6 ppm. With Dichlor, for every 10 ppm in FC it adds, it also increases CYA by 9 ppm. With Cal-Hypo, for every 10 ppm in FC it adds, it also increases Calcium Hardness (CH) by 7 ppm. These are chemical facts independent of the purity or concentration of the product.

cloudy water

Postby key » Sat 19 Jul, 2008 08:34

hello all...this is my third pool in 4 yrs and i have never had such a problem. first my pool(abouve ground 18x4) was great for about a month then it stormed(go figure)! i got algae and put some 50% algecide in the pool. It killed the algae but it left my water extremely cloudy. Its been almost 3weeks and I have used sink and sweep which did gather most of the particles to the bottom and my husband got in the pool and manually vacumed the bottom with the vacum hose without the attachment. this has cleared up a great deal but it is still cloudy. you can actually see the white particle floating. I did have a problem with the ph but that is fine now the chlorine is good. One day the pool with be beautifuly clear and have a huge gathering at the bottom of dead algae but once i vacum it up the clods persist. I have used clarifier, shock(which stained the bottom) and its still cloudy...the pool store isnt going to be much help cause all the levels are within range...what the heck to i do????? my kids are dying to swim and i dont know about you all but spending 350 for this pool then another couple hundred in trying to clear it up is mind boggling and pocket draining. i thought about draining it and starting over but the particles will probably remain. HELP

swimming in cloudy/shocked pool

Postby starsplitter » Sun 20 Jul, 2008 15:50

I am trying to clear my pool as well. It is finally blue, but cloudy. We are shocking it a lot, which seems to be doing the trick. Can we swim in this water or is there a time frame we should wait?

Pool Slave

Postby Pool Slave » Sun 27 Jul, 2008 18:20

Coming in late, but what a timely subject. I have all but lost faith in my local pool store 'experts'.

When I opened my pool June14th, it was nasty green, but after shocking it (1/3 times more than a normal weekly shock), it cleared up and was perfect. Fast forward to the week of July 18th. Started getting just the slighest hint of cloudiness and a tinge of green. Went to pool store with sample - no chlorine registering. After buying $82.00 dollars worth of balance, stabilizer, shock, algecide, and a chlorine 'stick' to put in the skimmer, my pool became a murky green mess. Soooo, back to pool store with a sample. Still had low chrorine. Told to scrub sides (which I already do on a regular basis), buy clarifier (to the tune of $15.00 a bottle) and shock again. The pool turned blue but was totally cloudy. Back to pool store with another sample. Told no chlorine and to use a flocculant ($20.00). Applied, recirculated all day and left pump off overnight so stuff would settle. The pool cleared up somewhat and I vacuumed to waste. Still not as clear as iI like it or has been in the past. Back to pool store with sample and told "no chlorine" and I must have "mustard algae" which "eats" chlorine. Okaaay. Bought heavy duty algecide (some sort of stuff with copper) and heavy duty (i.e. more expensive) shock. That seemed to do the trick, but 36 hours later I tested the water and it STILL registers no chlorine. So, I shocked again. Looks good now, but at the rate I'm going through the more expensive shock, I'm about ready to have the darn thing demolished and put in a jacuzzi! I have better things to do with my time AND money.

Um, sorry for the vent, but I feel the OP's pain.

Postby Guest » Sun 27 Jul, 2008 19:34

If you want to cut down on all these costs the best thing you can do is get a good test kit so you'll know what's going on in your pool.

Much of what a pool store sells you isn't needed or wanted for your pool. Unless you know your cyanuric acid level you can't accurately shock your pool. Without a good test kit you can't know what your cyanuric acid level is or what your free chlorine level is when you shock.

From the chemicals you listed adding, some will add other things to your pool that you may not want. The chlorine stick is probably trichlor which adds cyanuric acid and lowers pH. The shock you added will add either cyanuric acid or calcium.

High cyanuric acid levels make keeping algae away difficult. Low CYA levels and your chlorine is lost to sunlight very quickly.

It really is easy to maintain a pool once you know the basics. Relying on the pool store works if you have a good pool store nearby but I have found pool stores sell chemicals and don't always take the easiest route to a well balanced pool.
Pool Slave

Postby Pool Slave » Mon 28 Jul, 2008 06:04

Oh, I have and use test kits, but what's a person to do when the 'experts' repeatedly test your water and say you need this, that, and the kitchen sink? I'm a bit at their mercy - after all, they're the experts, right? sigh.

Anyway, for what it's worth, the CYA level is about the only one that has remained relatively level (but certainly something to keep an eye on). After I shock (Smart Shock), all levels are fine (including pH), but within 36 hours the chlorine tanks.

Water's looking good, though (for the moment). Su-weet...gonna be 99F today. 8)

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