My 6-year old is dying to swim and I've got green water even with high FC levels

I am in need of help clearing up my green pool water. I opened the pool 10 days ago to dark green pool water. There was no floating scum or anything, but the water was dark, dark green.

This will be my fourth summer with the pool and I have never seen it like this upon taking the cover off. At the beginning of the season, it usually starts out a light green that I can get cleared up in 3-4 days. I have been vacuuming and brushing daily ever since opening. I started out trying to keep my FC around 15, but it was losing so much each day that I could not maintain it. On about day 3, I started boosting it up to about 35 ppm so when it dropped, it was still above 15 ppm. So for the last 7 days, I have not taken a chlorine reading less than 18ppm. Testing twice a day, most readings were in the range of 25 – 35 ppm. Overnight last night, the FC dropped from 32 ppm to 23 ppm. I am not using my SWCG right now, just bleach. I have gone through a bunch of reagent with these high fc levels, but want to make sure the FC does not drop so I have been testing FC twice a day. Pump is running 24/7.

The water is now a light green and has been this same color for 3-4 days with no changes. It is actually about the color of bleach. I have been spraying off my cartridge filter twice a day and swapping it out with ones that have been soaking in the bleach/water solution every couple of days. The filter has been really dirty every time I have cleaned it until yesterday. Starting yesterday, there was nothing settled in the bottom and my filter was clean. After the first time the filter came out clean, I put in a brand new filter in case the problem was with the filter. Even the new filter is coming out clean. I know these cartridge filters are junk and this process was going to take a long time, but thought since I was getting brown stuff out every time, that eventually I would get there. Since I can’t get the green out of my water and my filter is not brown anymore, I am scared I am not killing any more algae even with the high FC levels. What do I need to do? I can’t see how anything could live in my pool. I can smell the bleach from about 20 feet away. My FC levels are not dropping as much as they were in the beginning, but like I stated before they are still dropping substantially overnight.

I am on well water so I would really rather not empty the pool and re-fill if at all possible. I do think I have some iron in my water, but it has not been too much of a problem in the past. Usually with high levels of chlorine, it seems to settle out and I can vacuum it up.

Here are my readings as of 22 May 2014.

FC = 23ppm
=> (I added a gallon of bleach after testing so this should be up to around 31-32 now)
CC= 0.5 ppm
TA = 80 ppm
CH – did not test since I have a vinyl liner
PH = 7.4
CYA was not checked.

In the past years, I have had trouble ever getting this above 30 ppm so that it will even register on my Taylor 2006 kit. I think I have read that algae eats stabilizer. Since I opened the pool to green water, I am assuming the little bit of stabilizer I had last year is probably gone. I suspect it is most likely 0. I was waiting to work on raising my stabilizer levels after I cleared up the pool, since the stabilizer lessens the effect of chlorine on algae.

I have never used anything but bleach and my SWCG to raise the FC. Baking Soda, Mule Team Borax, Salt, cyanuric acid and “PH Minus” are the only other things I have ever put in the pool. The PH started out good when I opened the pool, but was over 8 a couple of days ago, so I added PH Minus to get it back in check.

Any help in clearing up my water would be greatly appreciated. Is there something else I am missing? Green means algae, but I can’t seem to kill it. The walls and floor are not slimy if that makes a difference.
.

I can't suggest anything you're not already doing to clear the green but I do have a couple observations.

Save your FAS-DPD chlorine reagents by using an OTO testkit (yellow and red drops) for most of your frequent testing during this battle. The first couple times, do both FAS-DPD and OTO so you can get a read on the OTO color of high chlorine - it won't be on the comparator. Use the FAS-DPD once in a while to verify the OTO and, when you think the battle is won, to perform the overnight chlorine loss test.

As you note, filter quality could be a problem. See the Super Simple Recipie page for Amazon links to better filters. It's probably cheaper to buy better filters and remove some of the fine stuff than to buy chlorine to burn it all out.

High chlorine levels interefere with the pH test and bleach raises pH until it's done it's job. Don't adjust pH down (add acid) while the FC is above 10. If pH is below 7, however, you may consider moving it up with Borax.

The fact that the pool is consuming chlorine overnight and smells strongly of chlorine indicate that there's still a distance to go.

Stay the course, you will win this fight.
Good Luck, let us know how it's going.

This may be helpful to you -- a chart to help you interpret high OTO levels by color:

http://pool9.net/oto/

Thanks Dave. I have already ordered the Unicel filters from Amazon earlier this morning. I have an old OTO kit that I tried to use this morning as well as the FAS-DPD for your exact reasons. I diluted the pool water down with my well water (1 part pool to 9 parts well), but it is still reading off the color guage no matter what. The kit is 4 years old so I assume the drops may be bad. The FC was 23 ppm so if my dilution methodology is correct, I should have been reading somewhere between 2-3, which should have been in the middle of the kit range. I'll pick up another this weekend.

Thanks Watermom for the link. This may be easier than all the diluting anyway. It has always been hard for me to use those color charts. I never can decide what my "true" reading is.

So I guess I will just continue pouring the bleach to it. I thought I could eventually get it cleaned up, but when the filter started coming out clean after 12 hours of pumping and no more deposits on the bottom, I started worrying that I am not killing any more algae.

You will get it cleaned up, it will take a while, but you will. The filter may look and be clean, the stuff may be passing right through. Good job on the Unicels - let us know how it works.

Don't worry about accuracy with the OTO(undiluted) at high chlorine levels, just use the color chart Watermom linked and make a mental note of the color. You don't need accurate to know you've got alot (OTO orange) of chlorine. When you need accuracy (to check yourself and to determine when you're done) use the K-2006.

Thanks, Watermom, for fixing my typo - I though I'd proofread the post - sigh.

2-1/2 weeks in on 28 May 2014 and my pool is lighter yet still green. My Unicel filters are supposed to be in tomorrow.

Still not much in the way of filters being dirty or stuff settling out on the pool bottom. I am still vacuuming and brushing daily.

I decided to take my SWCG out of the loop since I wasn't using it anyway. I thought it might do it good to soak it in vinegar for a while and clean it up. I noticed that the tubes of the SWCG were nasty green and also that the intake and outlet hoses between the pool, pump, SWCG and back to the pool had a lot of dark green buildup in them. The tubes of the SWCG cleaned up pretty nicely with a heavy dosing of bleach and spraying them off.

However, the hoses that connect everything are not as easy to clean. All of the crevices seem to be caked with this stuff. They have gradually been getting darker and darker over the past couple of years, but have never seemed to pose a problem. They just look nasty!

At the end of the season last year, I soaked all of the hoses in bleach and water mixed in a large trash can before storing them for the winter. When opening the pool up and I was hooking everything back up, green flaky stuff kept coming out of the hoses. I cleaned it up the best I could by spraying with a hose pipe, but could only get about half of it out. I figured it would clean itself up after they started being used. After all, the pool has always been ready to swim in after about a week every year up until now. I am scared that I am re-introducing algae by using these nasty hoses.

Sorry I didn't not mention this earlier, but I completely forgot about it. Is there an easy way to clean these Intex hoses. I have no idea if they are different from regular hoses, but they are like a slinky and have a bunch of places for gunk to get trapped. I can't figure out a way to brush or clean them effectively. I plan on soaking them one at a time so I can continue pumping 24/7. I've got one hose that has been soaking in about 1/2 water and 1/2 bleach for about 6 hours and it doesn't seem to be doing anything so far. I've sloshed it around and sprayed with the hose pipe to no avail. Could this green film be algae since the hoses were stored over the winter and were completely dry? Can algae live with no moisture? Or is this green gunk, just green gunk?

Like before I have been keeping my chlorine levels really high. CYA is estimated at 0. My dad kept watch on the pool over the weekend as we were out of town. He cleaned the filter and brushed twice a day. He did not vacuum. He added 2 gallons of bleach every night (about 20 ppm in my pool). He didn't do any testing. When I got home, my FC was at 12 ppm. It had been about 36 hours since he added bleach when we got home so I am assuming this is the lowest it got. Here are my latest results 2 days after boosting the chlorine levels back up.

FC = 34 ppm
CC= 0.5 ppm
TA = 80 ppm
PH = 7.2

I just looked back and saw that you filled from a well. Wondering if part of this could be a metals issue, too. I'm gonna ask Ben to jump in on this thread to see if he has any ideas. Sit tight.

I think I do have some iron in my well water, but it has never caused much of a problem. I left the pool full over the winter so this is the same water that was in there for the past four years, with the exception of water that was added with the Intex venturi vacuum.

The green gunk in my hoses is a very thin layer and is dark green when wet. It isn't slimy. You almost have to scrape it off. When it is dry, it is a light green with a chaulky consistency. Before installing the hoses, I bent them around and shook them to break some of it loose. It looks like large green dandruff flakes.

BTW, Thanks Watermom for the high chlorine OTO color chart. Once I figured out what colors to expect by testing both ways a few times, it has saved me lots of reagent.

Not slimy, light green when dry, chalky.
Is it the color of the Statue of Liberty?
Have you used any pool chemicals containing copper - algecide, chlorine booster, etc?
Does the Intex Krystal Clear have a copper ionizer unit?

I think Watermom may be onto something regarding metals. I'm thinking that maybe dead algae or some other precipitate is stained with copper giving you a light green cloud. I recall PoolDoc has also metioned Iron staining green in some circumstances.

I've looked at Intex SWCG owners manuals. I "Think" all Intex SWCGs do have the copper ionizer. I KNOW most do.