Help me prevent frequent slamming

Brazillianguy

Gold Supporter
Sep 5, 2021
62
Miami. FL
Pool Size
15000
Surface
Plaster
Chlorine
Salt Water Generator
Hi everyone, I‘m looking for more information on more preventative actions to help me from having to slam often. So the current situation is that I find myself slamming my salt water pool too often. I believe that the reason is that I’m not doing appropriate preventative maintenance with balancing the FC when events happen. The situations that happen frequently is 2 things 1) my two small kids use the pool very often, as well as family using it over the weekends on occasion. 2) Here in Miami we get VERY frequent rain storms (this dilutes the chemicals, having to empty the pool occasionally to the correct level, as well as bring lots of leaves etc in the pool. My current maintenance practice is just weekly cleaning (brushing, cleaning out skimmer and pump basket, and balancing the chemicals.

My current testing shows me I need to SLAM. But after that ….. is there things I can do with those events that I mentioned earlier to be proactive instead of being reactive? Thanks in advance
 
Hi everyone, I‘m looking for more information on more preventative actions to help me from having to slam often. So the current situation is that I find myself slamming my salt water pool too often. I believe that the reason is that I’m not doing appropriate preventative maintenance with balancing the FC when events happen. The situations that happen frequently is 2 things 1) my two small kids use the pool very often, as well as family using it over the weekends on occasion. 2) Here in Miami we get VERY frequent rain storms (this dilutes the chemicals, having to empty the pool occasionally to the correct level, as well as bring lots of leaves etc in the pool. My current maintenance practice is just weekly cleaning (brushing, cleaning out skimmer and pump basket, and balancing the chemicals.

My current testing shows me I need to SLAM. But after that ….. is there things I can do with those events that I mentioned earlier to be proactive instead of being reactive? Thanks in advance
First step would be reviewing some water test results over the past couple weeks. If you are having to SLAM then that means there isn’t enough chlorine in the water.
 
  • Like
Reactions: Mdragger88
My current maintenance practice is just weekly cleaning (brushing, cleaning out skimmer and pump basket, and balancing the chemicals.
One action you can take is to test your FC, CC, pH more frequently than weekly. How do you know your SWCG is keeping up with the demands of swimmers, splash out and rain?
Here in Miami we get VERY frequent rain storms (this dilutes the chemicals, having to empty the pool occasionally to the correct level, as well as bring lots of leaves etc in the pool.
For most, the reason that they may need to drain the pool is because of high CH or CYA. Also, some that have very severe algae may also drain and replace water. Your water may not be that hard and since you have a SWCG, it is unlikely your CYA is high. It would be good to see your test results so we can provide better input to your issue.
 
  • Like
Reactions: Mdragger88
To elaborate on what @Bperry said -
The issue is definitely inadequate fc in relation to cya.
The question is why isn’t there enough fc?
It could be various things:
* Trying to maintain minimum fc instead of target 🎯 or a scootch higher FC/CYA Levels
*Swg set too low,
*Not enough cya to protect the fc the swg makes,
*Low salt condition causing periods of no production from the swg.
*Previous SLAM Process not actually completed
(all 3 end of slam criteria not met)

Since you are slamming now lets be sure you get it done right & hopefully never need to do it again
For a successful SLAM Process
you need to continue to MAINTAIN Slam level fc for your cya as often as possible (multiple times per day is best) until you meet ALL 3 end of slam criteria-

You are done when:

CC is 0.5 or lower;
You pass an Overnight Chlorine Loss Test
AND
the water is clear.
(Crystal Clear w/no algae dead or alive)

*Check & scrub every nook & cranny where algae may hide (light niches, steps, drain covers, ladder handrails, skimmer throats/weirs, etc.)
*Run slam level water through all water features & lines for at least a couple hours a day during the SLAM Process.
*Brush & or vac daily (this breaks up biofilms that algae uses to protect itself from chlorine)
*Backwash/clean filter when pressure rises 25%over clean pressure.
 
From my test yesterday. (Now remember that last rebalanced was last weekend where I put liquid chlorine to FC 8).
FC 0.5, CC 0.5, pH 8 (replastered the pool about 4 months ago), Alk 60, CYA 30 ( was higher before but i‘m sure with all the summer and daily rain and with evaporation and need to fill up pool etc.) Haven’t checked CH in a few months but it was in the acceptable range.
 
What is your pump runtime and SWG %?

Your SWG is not doings its job of generating sufficient chlorine.

Run your pump longer and your SWG at a higher %.

Your SWG should generate enough chlorine so your FC never drops below the minimums in the FC/CYA Levels
 
The low cya (below 60) will definitely leave your fc the swg produces vulnerable to being consumed by the sun in short order. Your swg is capable of producing 9.2ppm of fc in 24 hours so you shouldn’t need to supplement it if it is working properly. The average algae free residential pool uses 2-4ppm fc/day.
That said no swg can overcome an algae issue, even a powerful one, but they are often able to hide it for a while longer than an undersized swg.
As Herman mentioned, being proactive & checking fc every couple days would have shown you that you weren’t keeping up. An Overnight Chlorine Loss Test at target fc levels will show you if you indeed have an organics issue consuming your fc & need to slam. Unless you see visible algae then no need for OCLT just go straight to slam.
Is the water clear?
 
To elaborate on what @Bperry said -
The issue is definitely inadequate fc in relation to cya.
The question is why isn’t there enough fc?
It could be various things:
* Trying to maintain minimum fc instead of target 🎯 or a scootch higher FC/CYA Levels
*Swg set too low,
*Not enough cya to protect the fc the swg makes,
*Low salt condition causing periods of no production from the swg.
*Previous SLAM Process not actually completed
(all 3 end of slam criteria not met)

Since you are slamming now lets be sure you get it done right & hopefully never need to do it again
For a successful SLAM Process
you need to continue to MAINTAIN Slam level fc for your cya as often as possible (multiple times per day is best) until you meet ALL 3 end of slam criteria-

You are done when:

CC is 0.5 or lower;
You pass an Overnight Chlorine Loss Test
AND
the water is clear.
(Crystal Clear w/no algae dead or alive)

*Check & scrub every nook & cranny where algae may hide (light niches, steps, drain covers, ladder handrails, skimmer throats/weirs, etc.)
*Run slam level water through all water features & lines for at least a couple hours a day during the SLAM Process.
*Brush & or vac daily (this breaks up biofilms that algae uses to protect itself from chlorine)
*Backwash/clean filter when pressure rises 25%over clean pressure
Good points
I wanted to address some of them. Last I completed a SLAM was a few months back. All criteria was met. It definitely improved the FC generation afterwords. My SWG (which I upgraded to the 40k rated version) is set at 50%. I think I could be more on top of the CYA levels especially with the amount of rain I receive and amount of water refill needed with the heat causing evaporation. My salt levels have all been pretty good and I add fine granular pool salt when needed. I try to also clean my salt cell every 3 months. When I performed the slam before I brushed a few times a day. I have a dolphin robot that I use daily, BUT I don’t brush in the skimmer area, meaning removing the basket and brushing in that area. Do you do that weekly too? I think that I will try to check my chemicals biweekly for now and see how that helps (keeping up with the CYA, and FC), brushing inside the skimmer area. A question though, when kids swim often or when family comes over do you feel the biweekly checking and adjusting is sufficient? Should I increase FC a few points before > 5 people swim and test the FC when everyone is out?.. cause the 2 kids usually swim almost daily. How about with all the rainstorms? They are almost daily (they do drop leaves etc when we get those downpours. Should I set my SWG to superchlor once a week or more for those weeks? I really appreciate all the advice. Looking for the proactive things to do to stay ahead of mother nature and all. Lastly I’m sure that it helps with any organic growth with my pool temps being 88-90F.
 
I'll chime in here for a second on just one point. There is no reason a SWCG needs to be cleaned every 3 months as you're depleting the coating on the plates and shortening it life drastically. If the buildup is happening in the cell then your chemistry balance is off big time.
 
  • Like
Reactions: setsailsoon

Enjoying this content?

Support TFP with a donation.

Give Support
I would guess that most people with this issue simply keep their FC too low for their water conditions. Pools with a SWG should have a higher CYA than 30 or the sun will likely play a larger impact on your FC swings. There is literally no down side to running at the higher end of the FC/CYA chart, especially if you're not testing frequently and the pool usage or weather is erratic. I don't have a SWG, but my CYA is in the 40-50 range and I keep my FC up around 6-7 ppm. I have never had to slam.
 
The low cya (below 60) will definitely leave your fc the swg produces vulnerable to being consumed by the sun in short order. Your swg is capable of producing 9.2ppm of fc in 24 hours so you shouldn’t need to supplement it if it is working properly. The average algae free residential pool uses 2-4ppm fc/day.
That said no swg can overcome an algae issue, even a powerful one, but they are often able to hide it for a while longer than an undersized swg.
As Herman mentioned, being proactive & checking fc every couple days would have shown you that you weren’t keeping up. An Overnight Chlorine Loss Test at target fc levels will show you if you indeed have an organics issue consuming your fc & need to slam. Unless you see visible algae then no need for OCLT just go straight to slam.
Is the water clear?
Water is clear
 
I'll chime in here for a second on just one point. There is no reason a SWCG needs to be cleaned every 3 months as you're depleting the coating on the plates and shortening it life drastically. If the buildup is happening in the cell then your chemistry balance is off big time.
Actually I don’t see any buildup.. I just rinse it with a hose
 
My SWG (which I upgraded to the 40k rated version) is set at 50%. I think I could be more on top of the CYA levels especially with the amount of rain I receive and amount of water refill needed with the heat causing evaporation.
If you are testing CYA weekly, you should be able to maintain the requirement at 60-80ppm as it should not drasticaly change with just some rain. This would go along way to maintaining your FC levels in your pool. Therefore increase your CYA is one proactive step to take now.

Should I increase FC a few points before > 5 people swim and test the FC when everyone is out?.. cause the 2 kids usually swim almost daily. How about with all the rainstorms? They are almost daily (they do drop leaves etc when we get those downpours.
Testing before and after pool parties is always good to do and make adjustments, however if it is normal pool use (2 kids daily) then maintaining the FC at the upper end of the range based on the FC/CYA Levels should be fine. But still test every 2-3 days to verify that you have the SWCG set properly, the pH is in range, TA is ok, etc. Also test CH since you have not done that. All of this would be another proactive step to do now.
 
  • Like
Reactions: Brazillianguy
I would guess that most people with this issue simply keep their FC too low for their water conditions. Pools with a SWG should have a higher CYA than 30 or the sun will likely play a larger impact on your FC swings. There is literally no down side to running at the higher end of the FC/CYA chart, especially if you're not testing frequently and the pool usage or weather is erratic. I don't have a SWG, but my CYA is in the 40-50 range and I keep my FC up around 6-7 ppm. I have never had to slam.
I’ll do the OCLT and see.. SLAM it.. (since with the low CYA it will require less Chlorine) then bump up the CYA to higher end of FC/CYA chart and do biweekly monitoring. Let’s see how that goes. Thanks everyone for the info
 
do biweekly monitoring
Test your FC and pH daily while you are learning your pool. Summer FC demand will be (higher) different than winter. Use liquid chlorine to raise FC and SWCG to maintain. When you have swimmers, either add liquid chlorine or turn up your SWCG. During summer (pool is closed in winter), I run SWCG at 15% and I have a solar cover. If we pull the cover and swim, I turn the SWCG up to 50% for the day and it works great. If you have lots of swimmers, you can even test and add liquid chlorine in the middle of the day to keep it up.
 
Test your FC and pH daily while you are learning your pool. Summer FC demand will be (higher) different than winter. Use liquid chlorine to raise FC and SWCG to maintain. When you have swimmers, either add liquid chlorine or turn up your SWCG. During summer (pool is closed in winter), I run SWCG at 15% and I have a solar cover. If we pull the cover and swim, I turn the SWCG up to 50% for the day and it works great. If you have lots of swimmers, you can even test and add liquid chlorine in the middle of the day to keep it up.
Thank you
 
Wanted to chime in to give you confidence in the ease of the process once you get this down because it really doesn't have to be the burden of either a constant SLAM or perfectly regimented testing - once you get the hang of your pool.

I have a very similar setup in Tampa and have never had algae in the 18 months since building the pool. I test FC and pH every 5-10 days unless it needs significant adjustment. I test CYA around monthly to keep it in the roughly 60-80ppm due to my overflow and autofiller. I test CH and TA every 30-45 days, sometimes longer because it's so predictable. I throw the robot in once or twice a month. I only brush the corners and areas the robot can't get to maybe once a month, since I never have scale or algae that needs to be brushed off.

Things I learned about my pool, fill water, and chemistry to make it so easy to maintain:
1) Pool math app is very accurate - I don't test after adjusting anymore.
2) Higher CYA keeps FC more predictable - I always adjust to 80ish each time, and it's almost never below 60 by the time I get around to it again.
3) Little bit of muriatic acid every handful of days regardless of testing, since it's a predictable rise.
4) Always set the SWG to trend FC higher rather than lower - if/when it gets a bit too high, turn the SWG off for a day or two and retest. I also have it set to come on at 9am and turn off at sunset - that way I don't have to make as many seasonal adjustments for sunlight and heat.
5) Test and set FC a couple of days before and right after a big party, especially with kids.
6) Schedule waterfall to run for a bit daily to keep TA down since my fill water is high.
7) CSI in check prevents you from getting scale, so you should pretty much never need to clean your SWG, and it's easier to maintain pH with a healthy CSI rather than shooting for a particular number. Figure out where you can easily maintain pH, and only then adjust your TA/CH to maintain CSI at that number, since TA changes with pH so if you record TA with a low or high pH, it won't be accurate once pH is adjusted. I target 7.7 and then it tends to float up to 8 or even occasionally as high as 8.2 with still a healthy enough CSI. FC inefficiency at high pH is a myth because the effect is almost completely eliminated with the presence of CYA.
8) Large filter and never any algae means I can go a very long time without cleaning - all year if I wanted to, but I've been scheduling it twice a year.
9) Get 50ml containers from Amazon, then cut them into 25ml and 40ml so you can just dump them in your bucket and get the exact amount for each test. Also allows you to test TA at 50ml and get accurate within 5ppm.
10) Controversial TFP takes: I like borates and Orenda phosphate remover twice a year to further mitigate the risk for algae and scaling. Yes, you can have a perfect pool without it, but it's super cheap peace of mind with no downside - why not do it?

11) Grab a beer while I listen to my neighbors complain about paying $150/mo, brushing their pools daily, and still getting algae/scale regularly.

It'll be worth it when you get the hang of your pool because it's super easy from there! The hard work is just in that initial figuring out how your pool chemistry trends.
 
Last edited:
Wanted to chime in to give you confidence in the ease of the process once you get this down because it really doesn't have to be the burden of either a constant SLAM or perfectly regimented testing - once you get the hang of your pool.

I have a very similar setup and have never had algae in the 18 months since building the pool. I test FC and pH every 5-10 days unless it needs significant adjustment. I test CYA around monthly to keep it in the roughly 60-80ppm due to my overflow and autofiller. I test CH and TA every 30-45 days, sometimes longer because it's so predictable. I throw the robot in once or twice a month. I only brush the corners and areas the robot can't get to maybe once a month, since I never have scale or algae that needs to be brushed off.

Things I learned about my pool, fill water, and chemistry to make it so easy to maintain:
1) Pool math app is very accurate - I don't test after adjusting anymore.
2) Higher CYA keeps FC more predictable - I always adjust to 80ish each time, and it's almost never below 60 by the time I get around to it again.
3) Little bit of muriatic acid every handful of days regardless of testing, since it's a predictable rise.
4) Always set the SWG to trend FC higher rather than lower - if/when it gets a bit too high, turn the SWG off for a day or two and retest. I also have it set to come on at 9am and turn off at sunset - that way I don't have to make as many seasonal adjustments for sunlight and heat.
5) Test and set FC a couple of days before and right after a big party, especially with kids.
6) Schedule waterfall to run for a bit daily to keep TA down since my fill water is high.
7) CSI in check prevents you from getting scale, so you should pretty much never need to clean your SWG, and it's easier to maintain pH with a healthy CSI rather than shooting for a particular number. Figure out where you can easily maintain pH, and only then adjust your TA/CH to maintain CSI at that number, since TA changes with pH so if you record TA with a low or high pH, it won't be accurate once pH is adjusted. I target 7.7 and then it tends to float up to 8 or even occasionally as high as 8.2 with still a healthy enough CSI. FC inefficiency at high pH is a myth because the effect is almost completely eliminated with the presence of CYA.
8) Large filter and never any algae means I can go a very long time without cleaning - all year if I wanted to, but I've been scheduling it twice a year.
9) Get 50ml containers from Amazon, then cut them into 25ml and 40ml so you can just dump them in your bucket and get the exact amount for each test. Also allows you to test TA at 50ml and get accurate within 5ppm.
10) Controversial TFP takes: I like borates and Orenda phosphate remover twice a year to further mitigate the risk for algae and scaling. Yes, you can have a perfect pool without it, but it's super cheap peace of mind with no downside - why not do it?

11) Grab a beer while I listen to my neighbors complain about paying $150/mo, brushing their pools daily, and still getting algae/scale regularly.

It'll be worth it when you get the hang of your pool because it's super easy from there! The hard work is just in that initial figuring out how your pool chemistry trends.
Great info.. I really appreciate it… I just brought the orenda.. Have never used it before.. any tips? And you said about twice a year? How about the borates? How do you handle that?
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.