Controlling Pool Algae- Tapping the CFF Knowledge Base

Get Off My Lawn

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The pool was crystal clear for months. *edit to correct* The chlorine got low and some algae showed up, I found the auto chlorinator's top o-ring deteriorated. I shocked it at 10+ ppm and it yellowed and seemed to clear a bit. I ordered a replacement via Amazon prime. A week later they still hadn't shipped it. :mad: The algae took off. I got an oring locally, shocked it again @ 10+ppm, then its been at 5ppm for a week. Four days later boom a deep dark green, chlorine still at 5ppm, and all the other chemical levels are correct. Mama ain’t happy.
What say ye?
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Once upon a time I fought pool issues and got samples tested and they would sell me chemical after chemical but no changes. I brought home chemicals to precipitate everything out to the bottom and vacuumed it all away. Did it for years then adjusted chemicals after. Takes a bunch of backwashes but it solves it every time within days. I worked so well I didn’t even use a cover after that.
 
Once upon a time I fought pool issues and got samples tested and they would sell me chemical after chemical but no changes. I brought home chemicals to precipitate everything out to the bottom and vacuumed it all away. Did it for years then adjusted chemicals after. Takes a bunch of backwashes but it solves it every time within days. I worked so well I didn’t even use a cover after that.
I brought some home last night, the wife had already added some enzyme that’s supposed to clear algae. The flocculant’s going in tonight.
 
I think you need to add an algaecide and remove the dead algae in addition to high chlorine levels.
I haven't looked into it, the only agencies I'm familiar with is a copper base. I just got the metal stains out that had been there 6 months. I'm concerned about adding more metal stains.
 
Where's the pool boy? Is he busy? Isn't he supposed to handle that stuff?:rolleyes:
 
I’d shock it to 25 or even 30 ppm, brush like crazy the next day and run the filter for however long it takes to clear. You may need a coagulant to make the particles get filtered out. Also, if you don’t have one, you’ll need a complete tester kit to make sure everything else is in balance (residual chlorine would be an important test once you get it clear).
 
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How many hours does the pump run?
 
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Back when I had a pool we used baquacil instead of chlorine. With baquacil the shock component was high % hydrogen peroxide (21% maybe? Been a few years...)

The peroxide plus algecide would kill a bloom like that quickly. Then flocculant and vacuum and backwash and repeat....
 
Also, with the rains, you may have the Total Alkalinity out of bounds. Sam’s Club is the place for Baking Soda in bulk.
Alkalinity and PH are in the OK range, I've been getting the 12lb bags of baking soda for $8 and borax from wallyworld.
 
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We have a saltwater pool, I run the filter and chlorinator 12 hours a day every day, I shock it about once every 3 weeks, and I'll add about 2, 2 and 1/2 gallons of bleach every 3 or 4 weeks. That does the trick for us. If it starts getting green I do another shock.

You also need to make sure your vacuuming the dead stuff out.
 
Need to check how long the timer runs the system. Let us know? Anyway, make the system run nonstop until you clear it.
 
Here’s a summary of what you want to accomplish:
  1. Run the system nonstop until completely clear
  2. Shock the hell out of it until everything is dead and the water is clear
  3. Might need a coagulant to make the particles clump together and stick to the filter
  4. Brush the walls and floor to detach the crud
  5. Vacuum up the crud
  6. Backwash or clean the filter media

Then:

Check all values with a complete test kit and make sure EVERYTHING is in bounds (pay attention to Combined or Residual Chlorine which tells you whether your chlorine is actually able to do its job).
Run the system AT LEAST 10 to 12 hours per day in this heat.
 
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When you add flocculent to the water surface turn the pump off and let it settle for a day then vacuum and backwash over and over. When its clear you can reintroduce chemicals to balance. I sold my home to get away from the pool. Kids swam at the country club I never joined. Snob members hated they never joined and came as a guest. Boats and pools are work.
 
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Here’s a summary of what you want to accomplish:
  1. Run the system nonstop until completely clear
  2. Shock the hell out of it until everything is dead and the water is clear
  3. Might need a coagulant to make the particles clump together and stick to the filter
  4. Brush the walls and floor to detach the crud
  5. Vacuum up the crud
  6. Backwash or clean the filter media

Then:

Check all values with a complete test kit and make sure EVERYTHING is in bounds (pay attention to Combined or Residual Chlorine which tells you whether your chlorine is actually able to do its job).
Run the system AT LEAST 10 to 12 hours per day in this heat.
The CYA is in the OK range (the test strip just says "stabilizer")
The pool robot is running 3-6 hours a day with the fine filters installed.
I'm still not seeing liquid chlorine on the shelves, I just added a shock treatment for 20,000 gallons, in a 13k pool.
 
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You’re sure that pool is only 13k gallons? o_O

Assuming you’re sure about that
assuming you’re still at 5ppm
and that you’re using 68% calcium hypochlorite,

I’d dump in at least 5 or 6 one pound bags.

Is there a separate pump for the cleaner thingie and for the main pool pump/filter? The main pump and filter must run until you’re clear and then at least 10 to 12 hours in this heat.
 
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Is it a liner or concrete?

Do you run the filter all the time?

What do you normally use for chlorine?

Big question... how’s your cyanuric acid (if you use trichlor)?


The basics will be
A) Kill what’s in there
B) filter it out

You may be backflushing every couple hours.
-Fiberglass
-The pump is a variable speed pump that's on a timer.
-Tablets in an auto chlorinator unit. That's why the chlorine dropped, the top's o-ring failed.
-CY is in the OK range, so the total and free chlorine levels pre-shock.
 
You’re sure that pool is only 13k gallons? o_O
Assuming you’re sure about that
assuming you’re still at 5ppm
and that you’re using 68% calcium hypochlorite,
I’d dump in at least 5 or 6 one pound bags.

Is there a separate pump for the cleaner thingie and for the main pool pump/filter? The main pump and filter must run until you’re clear and then at least 10 to 12 hours in this heat.
Oops, is smaller, only 11.5K gallons.
https://www.tallmanpools.com/fiberglass-pool/1544/lagoon/tahiti
54.66% calcium hypochlorite
The pool robot's self powered https://www.poolzoom.com/dolphin-nautilus-cc-plus-robotic-pool-cleaner-with-pro-caddy.html
I'll check pump programming
 
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I’d still use 5 or 6 pounds. If you dump that in and run the MAIN pump and filter continually, the green should be gone tomorrow.
 
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The pool robot isn’t doing you any good until you kill the green and brush the sides of the pool. The only thing that’ll save you is the MAIN pump and filter (which is gonna need serious backwashing or media cleaning when this episode is done).
 
The pool robot isn’t doing you any good until you kill the green and brush the sides of the pool. The only thing that’ll save you is the MAIN pump and filter (which is gonna need serious backwashing or media cleaning when this episode is done).
The robot is running now to brush the sides and bottom. it has the 4 fine filters installed, and is currently sucking the crap off the bottom.
 
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But the real crap is suspended in the water. We need to kill it, let it float to the bottom so the vacuum can get it.
 
....... follow the instruction on the algaecide......if it says xxx amount per gallons and allow xxx amount of hours between this, follow it. Your pool may not clear up for a few days.....

You will need to run the pump more than normal and keep the filter media changed or backwashed. If it's a sand filter .......backwash and scrub any buildup a couple of times per day. If you have a cartridge filter, swap out the cartridge every day, while cleaning out and treating the algae infested one. Be sure it's 100% dry before you put it back into the filter. It's a good idea to have 4 cartridges handy anyway.

Green usaually isn't too big of a deal to get rid of....... The brown or Mustard algae can be a different story.
 
Or Gumbo. :D



we have a jail cook that was a Katrina transplant. My lord you want to talk about the best gumbo you will ever eat. The first time she made it she sent half the squad running for the toilets. They all kept telling her you're gonna have to calm it down.
 
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When you add flocculent to the water surface turn the pump off and let it settle for a day then vacuum and backwash over and over. When its clear you can reintroduce chemicals to balance. I sold my home to get away from the pool. Kids swam at the country club I never joined. Snob members hated they never joined and came as a guest. Boats and pools are work.
Never vac to the filter if you have a major issue like this one. Always vac to waste and keep an eye on intake levels. Backwashing is fine for standard clean up but big algae or silt always need to be vac to waste. Loads of good advice in here short of the one guy saying to ignore calcium hardness and other critical testing parameters for pool water quality. Get a test kit and buy chemicals from your local sams or costco unless you can get a deal set up with SCP or other distributor. Pool stores are a scam. I cleaned pools as a job from 12-21 and still keep my pool operators card current to this day. I did not stay at a holiday inn and the pool boy stories are all lies...
 
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Never vac to the filter if you have a major issue like this one. Always vac to waste and keep an eye on intake levels. Backwashing is fine for standard clean up but big algae or silt always need to be vac to waste. Loads of good advice in here short of the one guy saying to ignore calcium hardness and other critical testing parameters. I cleaned pools as a job from 12-21 and still keep my pool operators card current to this day. I did not stay at a holiday inn and the pool boy stories are all lies...
Slaps head- now I remember I made that mistake first time. I got out of that pool 15 years ago.
 
BTW.......the variable speed pumps are BS...... Your pump/filter needs to run enough to turn over the amount of gallons in the pool. A VSP will run at lower watts for more time and a regular pump will run at higher watts for less time.
 
I am grateful that other people go to all this trouble to keep pools operating... it's well worth the effort! :D
 
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I’d just keep shocking it. Backwash twice daily and it should begin to clear. Also, have you checked your stabilizer level(CYA)? If it’s too high, from chlorine tabs, your chlorine won’t be effective. If its too low, your chlorine will burn off faster than normal. We bought a house with a pool last year and it turned green about a month after we moved in. My CYA was too high, drained some, refilled, shocked the snot out of it and it cleared within a few days.


Sent from my iPhone using Tapatalk
 
I’m that guy.

I’d appreciate your input on this, you have a lot more experience than me. It seems hardness matters mostly on a concrete pool, or a pool with metal components (such as pipes or pump impellers, but do any of those even exist anymore?).

The wrong hardness can leach chemistry from the metals and certainly from concrete.

In a vinyl/fiberglass pool, with all plastic in contact with the water/filter system, is hardness something worth chasing in the modern age? Except of “swim feel” of the humans, it doesn’t effect things much, does it?
When CH is not balanced it causes all sorts of problems. There are tons of metal parts in lined pools like hand rails, lights, various types of hardware,ladders etc.
When CH is LOW you get eroding of tile grouting and de-laminating of plaster surfaces, Etching or pitting of pool decks or stone and concrete surfaces surrounding your pool, Corrosion of metal parts (i.e. pipes, ladders, filters, screws, etc.)
When CH is HIGH you get similar effects as high PH. The water will become baisic and become cloudy with calcium particles. This can lead to in severe cases clogged lines and filters.
So yes CH is important but in my opinion not as critical as alkalinity, ph, and sanitizer levels. I have experienced folks ignoring CH for years and then end up chasing their tails until they seek help and end up having to add loads of CH or drain the pool partially and fill with new water. Your advice minus the CH was solid advice. My advice is free and is not to be taken as me telling anyone what to do with out the guidance of a pool professional for their specific situation and pool. I am just a moron on the internet so please research what I say prior to making a decision.
 
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BTW.......the variable speed pumps are BS...... Your pump/filter needs to run enough to turn over the amount of gallons in the pool. A VSP will run at lower watts for more time and a regular pump will run at higher watts for less time.
But, but, but, CP&L/Duke gave us $300 credit towards the variable pump.
 
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