I Can't Get The Green Out Of My Pool

by Michelle
(Kern Valley, CA)

I have an Intex abg pool, 4,400 gallons.

CHL - 3
BR - 6
PH - 8.2
alk - 33
hardness - 80
cya - 30

Cartridge filter

My pool is green, looks like algae, lots of floaties, can't clear it. Tried shock, chlorine and algaecide. Now I haver some liquid Muriatic acid called Muriatic Magic, but am hesitant on my next step.

I have vacuumed and skimmed and washed out filter over and over for days. I can't find any other kind of test kits here, only the HTH kit.

Thanks for the question Michelle

Do you have a local pool store that you can take a sample of water to test? This might help out a bit. I'd encourage you to get a Taylor FAS-DPD K-2006 pool test kit.

Pool Water Testing

Water Testing Kit

Thanks for the readings. It helps to clear up your pool faster. The CYA (stabilizer) is fine, so don't touch that. And no chlorine tabs in the skimmer. Always use a floater.

The pH is a bit high. It should be between 7.6 - 7.8ppm, but now we want to get it down to 7.2ppm. Chlorine works better at a slightly lower pH. The alkalinity (TA) is low. It should be between 80 - 100ppm, 120 being the top.

Do you have a plaster pool or vinyl liner? With vinyl don't worry about the hardness. With plaster, you want the hardness between 150 - 250ppm. First thing is to raise the TA using baking soda.

Pool Alkalinity

Total Alkalinity

Start this process in the evening. To raise TA 10ppm per 1000 gallons you'd use 0.14 lbs. of baking soda. You need to raise your TA by 50ppm. Use 2.5 lbs. of baking soda in the deep end with the pump off. Let this sit for 3 - 4 hours, then turn the pump back on and keep in on for the remainder of the shock process.

Get the pH down to 7.2ppm. Start with 10oz. of muriatic acid broadcast around the perimeter of the pool with the pump on.

Swimming Pool pH Levels

Pool pH

Next is to shock the pool with chlorine 2 hours after adding the acid to adjust the pH. Remember that shocking is a process, not an even or a name.

Swimming Pool Chlorine

Pool Shock

Pool Chlorine

For 4400 gallons, use 1.5 gallons of liquid chlorine broadcast around the perimeter of the pool. Sweep the sides and bottom to break up any hot spots of chlorine. You'll want to get the chlorine level up to 12 - 15ppm. Go a little over, it's better than not hitting the 10ppm mark. Shock in the evening, then retest the chlorine and CYA in the morning.

You'll see how much chlorine has been used through the night. Keep filtering 24/7. During this process you can use a PolyQuat 60 algaecide as an added backup against any algae blooms that might occur.

The trick in clearing up your pool is to get the TA and pH in line and keeping the chlorine level above 12ppm for a period of time. That's why you shock in the evening, retest in the morning, then shock again. Be sure to clean the filters every day. Get new ones and swap them out with the old ones. Clean them, and swap them out.

Remember to test morning and evening and keep the chlorine level at 12ppm or above as best you can. When the pool turns a white/gray color and you only lose 1 - 2ppm of chlorine through the night you'll know the algae is dead. Let the filter do its job. And keep the cartridges clean.

If you have a pool store that's close, take a sample of water to be tested after every turnover of the water. This is normally about 8 hours. Morning and night. They should do it for free. Hope this helps and let me know how it turns out for you.

To post a reply, or if you have a similar question, you can see your post on the Q&A page in the "Algae/Green Pool Water" category.

Swimming Pool Questions and Answers

Check back to this post for updates or answers.


Click here to read or post comments

Return to Green Pool Water.

swimming pool care, basic pool care, above ground pool maintenance, inground, salt water

Click Here To Learn How This eBook Can Save You TONS Of Time & Money

Click Here To Learn The Best Way To Clear Up Your Pool 

Recent Articles

  1. White Slimy Film On The Bottom Of Pool

    the water was crystal clear but upon skimming the top we noticed a white slimy film completely covering the pool liner.

    Read More

  2. High Cynaric Acid

    My pool is a 26,000 gallon above ground vinyl liner. around 7/31/2014 the cya raised to 113

    Read More

  3. Can Super Floc Remove Pool Algae?

    Will raising the pH level and adding Superfloc get rid of algae?

    Read More