Can I slam every week to prevent algae ever returning

IrwinK

Well-known member
Apr 25, 2016
338
Orlando, FL
#1
Hi. Had my 1st appearance of green algae. I thought it was from pollen as robot vacuumed it easily.

Here were my readings on 4/25 when I began noticing it:

FC 4
TC 4.5
TA 60
CH 225
CYA 50
PH 7.5

I had been using pucks but have now stopped.

Slammed FC up to 24 and it has only dropped FC 1 and CC .5 overnight for several days.
Pool good now. Thanks TFP for all the info on slamming.

Now my question:

As I stopped using the pucks, I'm buying liquid chlorine in 2.5 gal. reusable jugs weekly.
Can I add the whole 2.5 gallons at one time without adverse affects.?

According to the Chlorine/CYA chart this would bring FC up to about 24 initially and then over a week back down to a 6 to 9 target range.

I wouldn't have to store the chlorine and this would be almost as easy as using pucks.
And I'd wouldn't have to worry about algae again.

Thanks
 

Flying Tivo

Well-known member
Jan 24, 2017
582
Monterrey, NL, Mexico
#2
I would just go for the SWG since you are already thinking about it. Yes you can drop the whole bucket, but TFP does not recommend that, too much of a swing and can cause damage to your equipment and plaster. If you cant get the SWG then opt for a stenner type pump for the chlorine!

Felipe
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,703
Tucson, AZ
#3
We do not recommend having chlorine levels that high all the time. It's basically wasting money as most of the chlorine is just getting burned off by the UV. Over time you are putting greater chemical stress on your equipment because FC is still FC - the CYA moderates the reaction rates but chlorine is still "attacking" everything in the pool. So, by overdosing the pool, you are basically exposing everything to a higher level of chlorine all the time. You can think of it like this analogy - going out in the sun can be a good a thing (Vitamin D) as long as you are moderated in your exposure; going out completely bare in the sun with no sun block on for hours on end will also create lots of Vitamin D as well cause advanced skin aging and skin cancer.

As the Greek Philosopher's taught -

Παν μέτρον άριστον, μηδὲν ἄγαν. (Pan metron ariston, meden agan.)

"Everything in moderation, nothing in excess."
 

needsajet

TFP Expert
LifeTime Supporter
Jan 4, 2016
4,558
Sydney, NSW, Australia
#5
I'll bet you have a good reason for what you want to do, so while I agree entirely with dosing (SWG or Stenner) to reduce the daily tasks, it might be an option for you to try adding FC every two days, then every three days, then twice a week, and see how it goes.

Not to mention the added stress on finishes and swimsuits, you'll find with weekly dosing that you lose most of the chlorine in the first two days, and then you won't have enough residual to last the rest of the week. Throw in a swim day or especially hot sunny weather, and it's almost assured your FC will fall below the minimum.
 
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IrwinK

IrwinK

Well-known member
Apr 25, 2016
338
Orlando, FL
#6
I'll bet you have a good reason for what you want to do, so while I agree entirely with dosing (SWG or Stenner) to reduce the daily tasks, it might be an option for you to try adding FC every two days, then every three days, then twice a week, and see how it goes.

Not to mention the added stress on finishes and swimsuits, you'll find with weekly dosing that you lose most of the chlorine in the first two days, and then you won't have enough residual to last the rest of the week. Throw in a swim day or especially hot sunny weather, and it's almost assured your FC will fall below the minimum.
Thanks everyone for all the replies. At first it seemed like a good idea.

Needsajet: What I didn't consider is the loss of FC at a more rapid pace at the higher levels.

If I'm losing 2 ppm per day at lower FC chlorine levels will this increase to 3 ppm or 4 or more a day at higher levels?
 

Blake1989

Well-known member
May 18, 2012
135
Birmingham, Alabama
#7
You don't need to SLAM every week anyway if your chlorine level is kept where it needs to be. Algae, most harmful bacteria, and viruses can't grow in a properly maintained pool. Just make sure you test often, and add chlorine when necessary.
 

needsajet

TFP Expert
LifeTime Supporter
Jan 4, 2016
4,558
Sydney, NSW, Australia
#8
It will depend on how much sun you get on the water, and how much swimming. It won't hurt to try it once and learn. Your screen would make a big difference I bet, but you still have to think about the downside of frequent high FC levels.

In my experience, yes, 5 ppm drop in full sun from a high level. I'm using post-SLAM experience, with a pool in full sun and daily or every other day use. My pool will drop from 28 to 12 ppm FC in 3 or 4 days. This would vary a lot from pool to pool.
 
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IrwinK

IrwinK

Well-known member
Apr 25, 2016
338
Orlando, FL
#9
It will depend on how much sun you get on the water, and how much swimming. It won't hurt to try it once and learn. Your screen would make a big difference I bet, but you still have to think about the downside of frequent high FC levels.

In my experience, yes, 5 ppm drop in full sun from a high level. I'm using post-SLAM experience, with a pool in full sun and daily or every other day use. My pool will drop from 28 to 12 ppm FC in 3 or 4 days. This would vary a lot from pool to pool.
I'll be doing a lot of testing and try to arrive at the proper amount of Chlorine to add every few days or more.

Also I have to compare this to how much the 2.5 gal jugs deteriorate sitting outside or in the garage. I have 2 of these. Used one and transferred the other to 1 gallon jugs and have them in the house.
 

needsajet

TFP Expert
LifeTime Supporter
Jan 4, 2016
4,558
Sydney, NSW, Australia
#10
You won't huge difference in the chlorinating liquid unless it's left in the sun or wasn't fresh to begin with. A couple months doesn't affect it very much indoors unless the temperature is high. I'll bet you get to an easy routine.
 
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IrwinK

IrwinK

Well-known member
Apr 25, 2016
338
Orlando, FL
#11
You won't huge difference in the chlorinating liquid unless it's left in the sun or wasn't fresh to begin with. A couple months doesn't affect it very much indoors unless the temperature is high. I'll bet you get to an easy routine.
Did the OCLT this a.m. FC dropped 1 ppm and CC was 1 ppm. FC 24 CC 1

Tested FC this evening and loss was 3 ppm for the day. FC 21 CC 1
 

needsajet

TFP Expert
LifeTime Supporter
Jan 4, 2016
4,558
Sydney, NSW, Australia
#12
That seems pretty good so I'm guessing your screen is keeping a fair bit of sun off the pool.

I wonder why you're getting CC at 1 ppm. Do you see that much CC when the chlorine is at your normal level?
 

Killer95Stang

Well-known member
Aug 17, 2012
758
Sunny SoCal
#13
Just bite bullet and get a stenner or swg system. I hope I'm not in the minority when I say I've never had algae. This is the start of my 4th season and i've never dealt with a slam, so to me its not normal.
 
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IrwinK

IrwinK

Well-known member
Apr 25, 2016
338
Orlando, FL
#14
That seems pretty good so I'm guessing your screen is keeping a fair bit of sun off the pool.

I wonder why you're getting CC at 1 ppm. Do you see that much CC when the chlorine is at your normal level?

Tested FC again this evening and loss was 3 ppm for a full 24 hrs. FC 18 CC 1 (Yesterday's reading was 3 ppm plus the 1 ppm from the OCLT = 4 ppm)

Pool temp is now 78. Full sun but very filtered through the fine mesh super screen.

Yes my CC readings were .5 before the high level of chlorine. It might be because of the time it takes to do the FC test. When I do the CC test the first 1 drop does makes it clear but a few seconds later on close examination there is a hint of pink and I add another drop.

Will see how my readings are as I get down to lower FC levels each day. I'm hoping for 2 ppm loss per day and .5 CC
 

JoyfulNoise

TFP Expert
Platinum Supporter
May 23, 2015
14,703
Tucson, AZ
#15
No, that's not right. If one drop turned it clear than it is 0.5ppm not 1ppm. The CC portion of the test suffers from color break through - if you leave the clear sample there long enough, the DPD re oxidizes to pink. This is why the test should be performed in under a minute. You do the FC test get it to clear (the clear is stable) then do the CC test. Once the CC part of the test goes clear, you stop and ignore any other color changes.


Sent from my iPhone using Tapatalk
 
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IrwinK

IrwinK

Well-known member
Apr 25, 2016
338
Orlando, FL
#16
No, that's not right. If one drop turned it clear than it is 0.5ppm not 1ppm. The CC portion of the test suffers from color break through - if you leave the clear sample there long enough, the DPD re oxidizes to pink. This is why the test should be performed in under a minute. You do the FC test get it to clear (the clear is stable) then do the CC test. Once the CC part of the test goes clear, you stop and ignore any other color changes.


Sent from my iPhone using Tapatalk
Thanks for the clarification. Then my CC is .5

- - - Updated - - -

Just bite bullet and get a stenner or swg system. I hope I'm not in the minority when I say I've never had algae. This is the start of my 4th season and i've never dealt with a slam, so to me its not normal.
Still evaluating. I'll probably get a SWG eventually. 1st season was pucks. This season is liquid chlorine. I'll make my decision for the 3rd season.

What I hope never to see again is Algae.

BTW, I'm getting the chlorine for $3.89 in 2.5 gal jugs at Ace Hardware.