Have to SLAM often to keep algae away...

[PoolBrews]

K,

Saltwater does not seem to hurt my lawns...

I have never shocked my pools.. If you maintain your FC and CYA per the saltwater tab of this chart, it is just not necessary.. FC/CYA Levels

Thanks,

Jim R.

I have to take exception to the comment "If you maintain your FC and CYA per the saltwater tab of this chart, it is just not necessary" (referring to shocking). I have had a pool everywhere I have lived for 40 years, and have always taken care of it myself.

I now own my first plaster pool (WetEdge), and have religiously followed the TFP method since opening a little less than 2 years ago. I cannot go any longer than ~40-45 days without my pool getting hazy, and chlorine begins to drop. I then have to SLAM, everything is back to normal in 3-4 days, and I'm good for another month and a half.

I can't keep my chlorine levels at the lower levels recommended - I need to keep them at 10pmm or higher or I can't even go 3 weeks.

I'm about to start a regimen of shocking with liquid chlorine once a month - hoping to avoid the full SLAM.

I never experienced this type of issue with my last two pools - both inground vinyl liner pools. I have no idea what causes this, but it's getting to be frustrating.

 

[cowboycasey]

I wonder if it is after a heavy rain or something to do with the pebble??

What CYA are you at?
How much CYA do you lose a month to the auto drain?
How much rain do you get a week?
do you have an overflow? (just read your Sig and you have an auto drain/fill)
How long do you run the pool pump?
What % do you have the SWG?
Do you have a robot cleaner?
Do you brush the pool 3 times a week or more?

Just trying to work with you and maybe we can find out what is happening...

I also have a vinyl pool (like you had) and keep my CYA at 80 and FC at 7, I run my SWG at 100% 8 hours a day now.. Mine is a 45k SWG for 15k pool..

Here is the rain questions answered, 4 to 8 inches of rain a month between may to Sep.. so unless you are adding CYA every 2 weeks your SWG can not keep up and FC is falling to fast... Poolmath shows you should be adding 1 pound of CYA every 2 weeks or 2 pounds a month to keep your CYA up.. (7000 gallons, CYA drop from 80 to 50)

Just looked at your Poolmath logs and you are going through exactly what I was thinking, the rain is depleting your CYA sometimes down to 40, when your CYA gets below 70 your SWG has a hard time keeping the FC level, the sun eats it faster than it can make it...

The Villages Climate, Weather By Month, Average Temperature (Florida, United States) - Weather Spark

In The Villages, the summers are long, hot, oppressive, and mostly cloudy; the winters are short, cool, and partly cloudy; and it is wet year round. Over the course of the year, the temperature typically varies from 47°F to 90°F and is rarely below 33°F or above 94°F.

weatherspark.com

So lets do some testing..

Can you take you CYA to 100 and continue to test it just like you are doing except when it gets to 80 raise it back to 100..

try keeping your FC at 8 or 9 with this CYA level and see what you get at the end of the month...

If you have doubts about your needing to SLAM go ahead and do a mini SLAM then take your CYA to 100 and when it gets to 80 add more..

How does that sound

 

[newdude]

I wonder if it is after a heavy rain or something to do with the pebble??

That’s where my mind went as well when I saw this earlier. It could all come down to runtimes. With a large SWG (well done !!) and a small pool I’m guessing that you have a good deal of downtime. After enough storms fall and get mixed ok, one storm finally hits in the 16 hours of downtime and the unmixed water goes bad before the pump and SWG turn on again. The bad water mixes and the good water goes cloudy.

 

[cowboycasey]

I wonder if running the VS pump 24/7 and the SWG running 24/7 at 20% or something... I think that with a CYA between 80 to 100 and FC at 8 it should keep everything good even with the rain..

 

[newdude]

I am the biggest fan of 24/7 there is. I watched all my friends go cloudy with the storms for 8.5 years and never had the issue myself.

 

[proavia]

Your PoolMath logs show a CC of 1.0 pretty consistently. Suggest you do an Overnight Chlorine Loss Test to help rule out a nascent algae bloom.

How many hours per day do you run your pump?
What exact hours is the pump running?
Are these hours all at one time or split up to 2 or more times daily?

What % is your SWG set to?
CYA of 60 may he a bit too low for a SWG pool in Texas. Consider raising to 70 or 80.

Have you checked to be sure your autofill is set to fill to the correct level and isn't overfilling cause water to exit the pool thru the overflow drain?

 

[Katodude]

So I would modify this advice just a little. I believe the OP has a screened in pool. The pool cage should provide some protection from the sun so I would advise against going to a CYA of 100. However, the screens will also grow lots of stuff that will wash into the pool when they have heavy rains. This is a high jolt of organics in a small pool.

I would run the pump 24/7, its a VS pump so that should not cost too much.
I would keep the CYA at 70 or 80 max. Buy extra reagent and test your CYA often. Small frequent additions this time of year are your friend.
Finally just run FC hot. Run it at 12% of your CYA. Keep it at that. With the pump running 24/7 and hot FC your should never have algae.

 

[cowboycasey]

sounds like a plan

I always forget about the screened in enclosures down there....

So I would modify this advice just a little. I believe the OP has a screened in pool. The pool cage should provide some protection from the sun so I would advise against going to a CYA of 100. However, the screens will also grow lots of stuff that will wash into the pool when they have heavy rains. This is a high jolt of organics in a small pool.

I would run the pump 24/7, its a VS pump so that should not cost too much.
I would keep the CYA at 70 or 80 max. Buy extra reagent and test your CYA often. Small frequent additions this time of year are your friend.
Finally just run FC hot. Run it at 12% of your CYA. Keep it at that. With the pump running 24/7 and hot FC your should never have algae.

 

[PoolBrews]

What CYA are you at? Typically I'm between 60 and 80.
How much CYA do you lose a month to the auto drain? I generally see a loss of 20/month - sometimes more.
How much rain do you get a week? A LOT right now. But this also happens in the winter with virtually 0 rain.
do you have an overflow? (just read your Sig and you have an auto drain/fill) I do.
How long do you run the pool pump? 12 hours / day
What % do you have the SWG? It's typically in the 15%-25% range depending on current chlorine level.
Do you have a robot cleaner? I do. I run it once per week.
Do you brush the pool 3 times a week or more? I brush once a week - when I run the robot.

I would be hesitant to bring CYA up to 100 - that's really high, and can cause an issue if I do need to SLAM. I believe that there is a chart somewhere that shows that even with CYA at 60 it's still reduces chlorine loss by over 90%.

Last year I ran the pump 24/7 to see if that would alleviate the issue, but it still occurred on frequent basis so I went back to 12 hours a day.

For nearly 40 years with vinyl liner pools, I had never experienced this issue. This has been a recurring issue with my new plaster pool... and I don't see where I am doing anything wrong.

 

[PoolBrews]

So I would modify this advice just a little. I believe the OP has a screened in pool. The pool cage should provide some protection from the sun so I would advise against going to a CYA of 100. However, the screens will also grow lots of stuff that will wash into the pool when they have heavy rains. This is a high jolt of organics in a small pool.

I would run the pump 24/7, its a VS pump so that should not cost too much.
I would keep the CYA at 70 or 80 max. Buy extra reagent and test your CYA often. Small frequent additions this time of year are your friend.
Finally just run FC hot. Run it at 12% of your CYA. Keep it at that. With the pump running 24/7 and hot FC your should never have algae.

This sound like a reasonable plan. I'm not used to checking CYA that often - it never used to change so much on me with my prior pools. I usually had to add CYA two or three times a year. Also, I didn't think that having CYA drop to 60 would affect me that much... I thought that the charts I saw still showed a 90%+ reduction in chlorine loss with CYA at 60.

 

[Katodude]

For some reason SWG like to have higher CYA. But every pool is different. Mine is very susceptible to black algae. For that reason I keep my FC high.

If your CYA is 60 try keeping your FC at 8 or 9 or even higher and see what happens. You might be having an incident that causes the FC to drop before you can measure it and that causes a problem. Somewhere there is a happy balance and you will find it.

 

[PoolBrews]

I had to SLAM on 5/23, then the pool got hazy and I had to SLAM on 7/4. During this time, my CYA did hit 40 on 6/16, but I brought it back to 80. My FC was at 14.5 at this time, and it never went below 11 during the entire time between 5/23 and 7/4. I thought with this high of a chlorine level that the CYA at 40 for a day or two wouldn't matter.

I would love to keep FC at 8 or 9, but I know that will trigger the haziness.

 

[cowboycasey]

there has to be something in the water that is not getting any or very little chlorine and starting an algae bloom.. are there any places in the pool with low or no flow?

 

[cowboycasey]

with lower CYA the chlorine is working more to kill things faster as less chlorine is suspended in the CYA... so with less CYA your higher FC is working better than a higher CYA... that is why this does not make sense.. as the CYA goes down the FC is harsher for you and everything in the pool including algae...

how does your cage look, is there any algae or anything suspended on it that would get into the pool when it rains daily? is there any algae somewhere on your deck or anywhere else that can be getting into the pool from other areas?

 

[Katodude]

This is a bit of a mystery. So two things that I can think of.

1. Testing error. Maybe its time for some new reagents, also get a speedstir
2. Run the pump 24/7. Pick an RPM where its not going to break the bank but keep that water circulating.

 

[PoolBrews]

I just got new reagents about a week ago, and I have been using a speedstir for the past year.

After my first SLAM, I did run the pump 24/7 for about 3 months. After I had to SLAM 2 times in 3 months anyway, I went back to 12 hours a day.

My pool is fairly simple in design - there aren't any areas that I can point to and say there is no circulation. I have pulled the light multiple times and cleaned it, but it never looks dirty or shows signs of algae, either on the light or the niche.

The cage is only 1 year older than the pool (about 3 years), and looks fine. No signs of obvious dirt or algae.

I'm a fanatic when it comes to testing and caring for my pool. I'm able to clear it up fairly quickly, but hate having to keep it at such a high FC level.

 

[Katodude]

Well it might be time to dig into the deep end a little.

But before we do that, can you post a bunch of pictures of your pool from different angles. Lets get a good look. There must be something we are missing.

 

[zea3]

Do you keep the auto fill turned on? Try turning it off for a few weeks and see if your pool loses water. You have added a lot of stabilizer over the summer and it normally doesn't deplete that quickly or that much.

 

[cowboycasey]

@zea3 they get up to 6 inches of rain per month from may to Sep.. I doubt the auto fill even turns on for 6 months a year

 

[PoolBrews]

Exactly. My water bill hasn't changed over the last 6 months - it's not running