Very Green Water since last two months

[ripplev]

Hi,

My water is very green. Since last two months I have been adding shock, bleach etc but no change.

Here are my readings:

FC - 8.5
CC - 1.0
PH - 8.0
TA - 250
Cal - 200
CYA - 0

Any help will be greatly appreciated.

[Simmons99]

You still have CC reading - which means that you have organic matter in the pool. With a CYA level of zero, you want to bring up the chlorine up to at least 10ppm and test VERY frequently to bring the level back up - if you let it yo-yo the algae will grow back while the chlorine level is low.

Also - if this is an outdoor pool - the CYA of zero means that all of your chlorine will be burned off when the sun is out. You may want to add until you get to 20-30ppm of CYA (BUT make sure you check your CYA reading before adding - you don't want too much)

[ripplev]

Thanks Simmons,

So should I add one more gallon or Bleach considering I've 25 feet (round) above the ground pool.

With this do I need to add anything else?

[finch]

I wouldn't want you to do anything based on a statement I make, but perhaps someone could comment on the ph. Doesn't the high ph greatly reduce the effectiveness of the chlorine? Isn't there a problem maintaining hypochlorous acid levels at a ph like 8?

[ripplev]

I added 3 more gallons of chroline today still no change in readings. Something is eating my chlorine out really fast.

Any comments?

[finch]

While waiting for others to respond:

Have you doublechecked your cyanuric acid level and if it is actually zero why do you have no cyanuric in an outdoor pool? This is sold as stabilizer or conditioner and should say cyanuric acid as ingredient. If cyanuric levels are zero chlorine is quickly destroyed by sunlight. This is also why it is often recommended to add chlorine in the evening, though if you need to add during the day to make sure levels don't drop you should do so. I suspect others are going to say that 8.5 free chlorine is not high enough for an algae problem. Hopefully others will come in and give advice for amounts and proper chlorine levels given your ph etc.

[finch]

"still no change in readings. Something is eating my chlorine out really fast."

How long after you have added the chlorine are you checking and finding that the reading hasn't changed?

[ripplev]

Here are latest readings:

FC - 6
CC - 1
Ph - 7.8
Alk - 260
Cal - 320
CYA - 0

Should I decrease PH or increase CYA before adding more Chlorine. I know I can use Muratic Acid to decrease PH but to increase CYA is there any product I can buy from regular store?

Should I put bleach first to increase chlorine?

Any suggestions?

Please help.

[mbar]

Your alkalinity, ph and calcium levels are all high. Along with no cya, you will not be able to hold any chlorine in the water long enough to kill what is growing. What have you been using to chlorinate your water? If it is cal hypo, that is what has your calcium levels so high. If it were me, unless your fill water is high in calcium and alkalinity,I would drain the pool down 1/3 and refill three times. This way your calcium and alkalinity would be lowered. Then you can add stabalize (cya) enough to get you to 30 - 50. You can buy this at any pool store, walmart or lowes. This way you will be able to hold chlorine in your pool. These are the numbers you want to have in your pool:
FC 3 - 5
CC 0
PH 7.4 - 7.6
Alkalinity 80 - 120
Calcium (not necessary in a vinyl liner pool) sot higher than 400
CYA about 30 to 50

Hope this helps, feel free to ask any questions you may have.

[finch]

I'm no specialist in these things but I think you have a couple of key problems.

Don't go dumping a crapload of cyanuric in the pool though. Too much can be as bad as too little. If you are sure that your cya/cyanuric test is correct then I would get some stabilizer. You can get it at wal-mart. It sounds like you have a solid test kit, but if you are using test strips to test for cya they can be very inaccurate and you might want to get the number checked at a pool supply store.
It takes up to a week for it to fully dissolve and mix in the pool, so I would start with trying to raise it 20 ppm or so, if it is truly around 0 now. A small amount has quite a beneficial impact and you don't want to overshoot by trying for 30-50 at one go. Once you get it near 30 I would leave it alone.
I also think your ph is too high and it is hindering the effect of the chlorine. I don't know what above ground pools are recommended to have, but I doubt that 7.2 would be a problem. Again, don't go crazy with the muriatic. You don't want it dropping below 7 for significant amounts of time. It can take a day or so for the reading to stabilize. Try to bring it down by .4 or so(so it is around 7.4) and then see what happens. Algae bloom can cause ph to creep up also so keep an eye on it.

While this is going on don't let your chlorine drop or you will get more trouble. To really clear the pool I suspect you will need to get your chlorine up to 15ppm or so and hold it there for a few days and run the pump. Again, I don't think this should be a problem for an above ground liner pool, but hopefully someone will comment if it is. If it is dropping through the day and there is someone home to check it they may have to add some during the day. If the chlorine drops too much it takes only a few hours for you to be right back where you started.

[mbar]

finch is right on. In order to kill an algae bloom completely you have to maintain a shock level of chlorine and let the pump running 24/7 for a couple of days till the chlorine level stays level overnight. Checking as often as you can during the day to get the levels back to shock. If it is true that you have no cya in the water, you will have to add bleach all day when the sun is shining as the sun eats up the chlorine that is not stabalized too. Finch is right, it can take up to a week for the cya to show up - add enough to get to 30, most people like to run their pool between 30 - 50.

[ripplev]

Thanks everyone for your help.

I added some hth ph decreaser and stablizer yesterday.

My water is blue now but still very cloudy.

Here are my latest readings:

FC - 7.5
CC - 0.5
Ph - 7.5
TA - 250
CYA - < 5 ppm (I added stabilizer (HTH Stabilizer) last night in skimmer so I believe this should take about week to give me good readings. But I can definetely see some difference today in my CYA testing. Last night I was able to see the black dot very clearly, today I can still see it but its getting little fuzzy.

Let me know if I need to add any more chemicals except bleach.

[Watermom]

Your alk is too high. Read the sticky at the top of the alk forum for directions for lowering it.

[finch]

"Let me know if I need to add any more chemicals except bleach."

The less the better with most chemicals. I think you are on track so I wouldn't fiddle with much.

At this point you mainly need to stay on top of the chlorine level and make sure your ph doesn't stay up above 7.6. I would hit it with more chlorine to get the fc level to 10-15.

The most important thing is to not let up, even for half a day. It is a good sign that the pool is less green, but milky. You are killing the algae, but until the pool is clear and you have brushed and killed anything on the liner you don't want to let up or you could lose control of it again.

I would stay focused on solving the algae problem first. Then the total alkalinity can be eased into shape. I think the recommended TA would be about half what it is at the moment. Be sure to follow the advice on this forum of lowering ph and aerating to bring ph back into range:

http://www.poolforum.com/pf2/showthread.php?t=191

or you could get yourself on a treadmill and never permanently lower your TA. I got caught on this treadmill half a dozen years ago. It cost a few hundred dollars before I finally threw up my hands and got off. I simply lived with the high TA, which crept down over the next few seasons, but now understand the solution.