Algae present for the first time - where to start

Jun 3, 2022
5
Northern CA
Gunite pool
15k gallons
Pool temp: 76-78
Pool filled: May 2022
Taylor K2006 used for testing

When swimming yesterday we noticed faint areas around the deep end step that looked slightly green/yellow and dirty. This is the first time experiencing algae and I just want to nail down where to start first. I have posted my numbers here from last night. I obviously need to adjust a few things but when algae is present (see photos, it’s not overwhelming-yet!) where should I start first? I added about 3lbs of baking soda last night and ran the pump all night in hopes to start increasing my TA but when testing the water this morning it is still 50. My PH is 7.6 this am and my CYA is actually closer to 70 (high, I know).


What should I do first? Do I add more baking soda to raise my TA then shock?

Do I shock first then worry about the rest? And if so what order is best.

Any suggestions or guidance is appreciated. Thank you!
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Your TA is fine for the moment.

Your CYA is 80, use that, always round up. FC 3 is low for CYA 80...Always follow this...Link-->FC/CYA Levels

Add 5ppm of liquid chlorine now.

It is likely algae. If you are sure it is algae, then follow this process. Link-->SLAM Process

Print it out, read it three times, follow the instructions.

If you are unsure if it is algae, the you can do this test....Link-->Overnight Chlorine Loss Test

Doing the test may save some $ by avoiding SLAM if it is not necessary.

You fail, then SLAM. If you pass, could be some other kind of staining.

Is it slipery? Slimy? Then it is algae, start the slam.
 
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Your TA is fine for the moment.

Your CYA is 80, use that, always round up. FC 3 is low for CYA 80...Always follow this...Link-->FC/CYA Levels

Add 5ppm of liquid chlorine now.

It is likely algae. If you are sure it is algae, then follow this process. Link-->SLAM Process

Print it out, read it three times, follow the instructions.

If you are unsure if it is algae, the you can do this test....Link-->Overnight Chlorine Loss Test

Doing the test may save some $ by avoiding SLAM if it is not necessary.

You fail, then SLAM. If you pass, could be some other kind of staining.

Is it slipery? Slimy? Then it is algae, start the slam.
Hi! Thank you. My husband was in the pool yesterday with goggles and said it looked like dirt and moved easily. It was not slimy or slippery. I will say last night when testing my FC was 3 and this morning it was still 3. Should I still do the overnight test? My in-line chlorinator was not shut off over night but the tabs inside are gone so not sure that makes a difference.
 
Add 5ppm of liquid chlorine now, get it up and keep it up. Follow the FC/CYA recommendations.

Do the OCLT. Follow the instructions.

Are you using pucks to chlorinate? With a CYA of 80, it will take a bunch of chlorine daily to keep your FC up. Pucks add CYA to the pool. You are getting close to the point you won't be able to keep the pool sanitized and will have to replace water.
 
Let's do a proper OCLT. Get FC up. Print out the instructions, read them 3 times, follow to a "T" Having printed really helps...

Then we can decide proper next steps...
 
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