Serious problem with Algae

Jul 30, 2007
5
Hello all... I'm new to the forum and also fairly new to having a pool.

I have a serious Algae problem. I'm at the point that I want to close the pool for the rest of the year. I had the same issue last year. I've been living in my house for about 2 years now. So, I assumed the previous owner never replaced the sand in the filter and I was told my pump was too slow (3/4HP). Therefore this year I replaced my Hayward pump & sand filter to a new Hayward 1.5HP super-pump and a new S220T Sand filter with new sand.

At 1st I thought it was some of the tree branches that were hovering directly above the pool. I hired a tree guy to cut all of them down. I thought that would fix my issue, but unfortunately it didnt. I've been trying to elleviate my algae issue by continuously shocking the pool and taking my pool sample to my local pool store. Last night I put in 3 gallons of regular 6% ultra liquid bleach. I just took it this morning and this is the readout they gave me:

FC = 6.7ppm
PH = 7.6
Hardness = 0ppm
Alkalinity = 63ppm
Cyanuric Acid = 25ppm

Please somebody tell me what am I doing wrong... HELPPPPPP !! :)
 
Welcome to TFP!

To kill algae you need to bring the FC up to at least 12, given your CYA level, and hold it there for a while. Some kinds of algae may require even higher FC levels. You really need a test kit that is able to read FC levels above 10, since you will need to test the FC level and bring it back up to 12 several times a day to really get ahead of the algae. Keep doing that until the FC level holds overnight, you don't have any CC, and the algea is either bleached out or gone.

While you are doing that you should run the pump 24/7, brush the pool once a day while the FC level is high, and keep an eye on the filter and backwash/clean the filter as needed.

What does the algae look like? Murky green water?
 
The bottom line is you aren't putting enough chlorine in the pool.

You need to be able to test for yourself to get anywhere with pool maintenance. Raise your chlorine to 15ppm, and then check it and add more as required at least every 8 hours. Run the filter 24/7 and brush the pool daily until it's clear.

Your 25ppm CYA reading is suspect since you have algae problems. It's probably lower than that, maybe 0ppm. The cloudiness in the water can mess up the test.

With low CYA, sunlight rapidly consumes your chlorine, which gives you no sanitation by the end of the day. How do you chlorinate the pool normally? Feeder, liquid, floater? Once you get the mess cleared up, always make sure you have at least 3ppm of free chlorine. If it drops to zero, even for a few hours, algae will start and you are back on the road to a green pool.

3 gallons of 6% bleach isn't nearly enough to shock a 30,000 gallon pool. 9 jugs (they aren't usually gallons) is about right to start.
 
First, as a pool owner, buy your own comprehensive test kit. Don't ever trust pool store tests. The TF-100 kit sold in these forums is the best investment you can make for your pool. It's the same professional testkit sold by Taylor, just repackaged nicer and with extra amounts of reagents.

Before you even shock the pool with the appropriate amount of chlorine, you need to balance everything else in the water. I would order your testkit first before you do anything. Then you can go from there. These forums were a godsend for me.
 
Wow, this is excellent! Thanks for the rapid response.

When I looked this morning, the color of my pool was murky green, like you mentioned.

Well, after I went to the local pool store this morning and got the pool water readings I bought
a 24-pack box of powder form super-chlorinator with 68% available calcium hypochlorite.

I went home afterwards and did the following:

1.) Backwashed the pool (the water was murky green)
2.) Poured (7) of these 1lb-super-chlorinator packs into my pool

I hope that wasnt too much. I do need some type of water tester that would tell me the actual water
read-outs for everything.

I have some questions for you:
=====================
1.) Do you have any recommendations for a good water tester & where I can get it?
2.) Should I continue to backwash even though the psi-gauge stays the same as started at 20psi?
(I was told to backwash in the morning and the evening to clear the algae)


Thank for your help.
-O
 
see my signature for a great test kit, and some other tools to help you get your pool into shape!

ETA the 7# of calHypo boosted your FC by 18. if your FC was 6.7 this morning, you now have 25ppm.. Use Jason's calculator to better help you add the correct amounts.

Most here shock with bleach, and also use it for their regular source of chlorine! Usually much less expensive than the pucks or powders, which add things you usually don't want as well.
 
I had some really good luck with 10% chlorine I got at home depot. It cleared up a VERY nasty Green Algae infestation. I pushed the chlorine level up to about 20PPM with a CYA of 30. I also brought the PH down to about 7.0 - 7.2. My thinking on the Chlorine was it was going to get used up really quickly so going a little higher wouldn't be catastrophic.
 
Thanks everyone for your info. Okay great, i'll order a TF-100 test kit ASAP.

My source of Chlorination:
=================
I usually use (3) of the 3" puck floating-chlorinators for my chlorine source.

There is a homedepot close by my house. I will go this week to pick up a case of 10% chlorine.

When I get home this evening I plan to:
==========================
1.) Get my CYA to at least from 20 to 40ppm
2.) Get my CH from 0 to 200ppm
3.) Get my TA from 63 to 90ppm

My Question is:
==========
1.) Does it matter how you put the chemicals into the pool?
2.) Is there a time limit between each chemical?
3.) Can they all put in at once or would I need to wait..?



Thank you,
-O
 
If you continue using trichlor pucks the CYA will go up, since the pucks contain CYA. At low CYA levels this is handy, but eventually your CYA will get higher and could become a problem. Aiming for CYA of 40 is great, just be aware that the pucks will increase CYA and might cause you to overshoot.

Since you have a vinyl liner, and assuming none of the concrete is directly exposed to the water, there is no need for CH.

As long as you are using pucks for chlorine you should bring your TA up to between 100 and 120. If you are switching to liquid chlorine/bleach then TA should be between 70 and 90.

You shouldn't raise PH or adjust TA on the same day as adding CH. For the most part other chemicals just need a half hour to mix in with the pump running between additions.
 

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oskillz said:
There is a homedepot close by my house. I will go this week to pick up a case of 10% chlorine.

Remember that when it comes to liquid chlorine, be it 10% from home depot, 6% ultra-bleach from walmart, 5% clorox bleach from the grocery store or 15% "liquid shock" from the pool store, it's all the same stuff...just different concentrations.

Chlorine is chlorine is chlorine. Do a little math, adjust the dosage and buy whatever is cheapest. The Walmart 6% Ultra is the best bang for the buck in my area. A 174 ounce jug goes for for $2.49, which is $1.83 a gallon. Compare that with 15% "Liquid Shock" from my local pool store at $9.49 a gallon and you see why BBB works! :p
 
The 3" pucks don't dissolve well in floaters. They are designed for erosion feeders. Using them in a floater often results in under-chlorination. If you've been using them, I'd be surprised if your CYA isn't high. I wouldn't make any changes to CYA level until you have a second test result.
 
Thanks again everyone for all of your input. I just ordered the TF-100 kit. On average, does anyone know how long it would take for shipment? Keep in mind, I live in New Jersey.

I checked my pool this evening and looks like the heavy shocking is working. The pool color has turned from a murky green to a really light color green. I also added another 2 gallon jugs of 6% bleach just to make sure the FC stays really high in order to rid the algae. We'll see how it looks tomorrow morning. I also added 5lbs of TA earlier.

I would need the TF-100 test kit to get accurate readings to post on here. Hopefully it should come soon.
 
Thanks to everyone for the nice words and thanks for the kit order.

The kit will ship today UPS ground and should be delivered Friday afternoon to NJ

As an aside, I will soon modify our site to reflect Same Day Shipping on all orders received by 3:00pm Eastern Time. We've been doing that for a month or so but didn't want to publicize it until I knew we would be able to perform consistently.
 
Excellent! Thanks Dave & everyone. I look forward to receiving the kit soon.

Btw, my pool looked a lot lighter in color this morning. Its almost clear but just a little bit cloudy.
I'll continue to add the 6% bleach in it to just keep the FC high until I recieve the kit to get the actual readings.
 
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