Help with algea
- Thread starter Kivare
- Start date
- Jun 24, 2021
- 16,258
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
You continue to kill algae. Some will be consumed by the sun, but allowing the FC to drop during the day extends the length of the slam.
Test and add every 1-2 hours when you can. Will go faster.
SLAM on!
- Jun 8, 2019
- 4,581
- Pool Size
- 20000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
In case it wasn't clear - you're not just dumping some chlorine in once a day and hoping it takes care of it.
You should be testing often, at least 2-3 times a day but once an hour if possible. When you test, you find out how much FC you have. Then you add more, enough to get you back to the SLAM level for your CYA on the FC/CYA Levels.
If your CYA is lower than 20, add another 10ppm in a sock by the return. It will take 2-3 days to show up on the test, so just figure you're at 30 and use that FC target of 12 with each addition. Then after 2-3 days, test again - if it's higher than 30, adjust your FC target to the new CYA level.
You should be testing often, at least 2-3 times a day but once an hour if possible. When you test, you find out how much FC you have. Then you add more, enough to get you back to the SLAM level for your CYA on the FC/CYA Levels.
If your CYA is lower than 20, add another 10ppm in a sock by the return. It will take 2-3 days to show up on the test, so just figure you're at 30 and use that FC target of 12 with each addition. Then after 2-3 days, test again - if it's higher than 30, adjust your FC target to the new CYA level.
It's been a while since I posted, and had to start over fresh because chlorine dropped too low and algae flourished. So here is an updated picture of how it looks so far after about a week of adding chlorine and checking multiple times a day. How do you think it is coming along?
- Jun 8, 2019
- 4,581
- Pool Size
- 20000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
What are your current levels? How often are you checking and what FC level are you adding to target?
It's definitely less green than it was. Just keep up with the chlorine additions as frequently as possible. Each time your FC drops below SLAM level (40% of your current CYA level), the algae gains a foothold. Stay on it and it'll be blue again in a couple of days. Then it will start to clear.
ph is about 7.8, cya is 40, fc was 11.5 last time I checked about an hour ago and added 3 gallons of chlorine. checking about every hour or two, and fc level is 16 trying to target. Just check fc and it was 15.
Last edited:
- Jun 24, 2021
- 16,258
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
I have the same basic setup. With a 30K pool and sand filter, it just takes longer. You got this...
Yes, I feel more confident about what i'm doing and seems to be moving in the right direction. I can't wait to use our pool again.
The good news is, it's safe to swim as soon as you can see the bottom at the deepest point. It's safe to swim with FC at SLAM levels, so you don't need to complete the SLAM first.
- Jun 24, 2021
- 16,258
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
That’s lots of improvement. How often are you backwashing? How do you decide to backwash?
We’re doing it more at first when returns would run slow now they are running better so not so often. Last time was a couple days ago.
- Jun 24, 2021
- 16,258
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
Note your clean pressure. Say it is 10psi. When it rises 25% to 12-13, backwash. Should be good to go. Just at least check it maybe more often, that may help.
How much chlorine is in it right now? You had a really green pool and it takes a lot of chlorine to get rid of green.
DanF
Silver Supporter
- Mar 17, 2019
- 612
- Pool Size
- 12500
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
That's a TON of improvement! Keep adding liquid chlorine...no shock, tabs, or stabilizer and follow the backwashing instructions above.
You're done once you meet these 3 criteria:
- Clear water
- CC less than 1.0
- You pass an OCLT
You're done once you meet these 3 criteria:
- Clear water
- CC less than 1.0
- You pass an OCLT
Edge70
Well-known member
As others have said, stick with it. I've been where you are now... not long ago. I think the main issue now is that you have a pretty large pool and it takes a long time to clean it up with the sand filter. Here's what my pool looked like on May 19th. You can see it has the same dull look with lack of clarity.
And here's how it looked on June 10th.... I would say it's even clearer now a week and a bit later.
Like you, I was pretty frustrated and questioning the progress but it works... just takes a long time! You may want to try doing a deep clean on the sand filter. You'll be amazed how much Crud comes out of it. Make sure you run the filter 24 hours a day. Don't skimp here to save on utility cost. Just keep that pump running, and keep FC in the right spot and you'll get there. 100% it's expensive to get the pool back in the right condition which has motivated me to ensure that I don't have this situation next year when we open. Good Luck!
And here's how it looked on June 10th.... I would say it's even clearer now a week and a bit later.
Like you, I was pretty frustrated and questioning the progress but it works... just takes a long time! You may want to try doing a deep clean on the sand filter. You'll be amazed how much Crud comes out of it. Make sure you run the filter 24 hours a day. Don't skimp here to save on utility cost. Just keep that pump running, and keep FC in the right spot and you'll get there. 100% it's expensive to get the pool back in the right condition which has motivated me to ensure that I don't have this situation next year when we open. Good Luck!
What’s a good rule of thumb for the amount of time to backwash and filter?
Filter 24x7 at slow speed at a minimum. Only backwash when the pressure rises by 25% after the last backwash.