How many SLAM's a season do you do?

[bmj0928]

Does anyone else have to perform multiple SLAM's a season?

It seems like I am constantly slamming my pool. If I let the chlorine drop below recommended even for a day, I seem to get a cloudy pool. I have scrubbed everything down, tried to find the hiding places, and even got new filter cartridges. I added enough LC this morning to expect an 15ppm rise, but ended up seeing a 22ppm rise. The pool is looking clearer, now, but usually the "effects of adding" calculator is dead on. My CYA is 50, but I may try to do a drain and refill to get it down to 30 or 40.

 

[cowboycasey]

I have done 2 SLAMS in 8 years... Think of the minimum as a CLIFF, you NEVER want to drive off a CLIFF...

For a CYA of 50 you want to keep you FC level between 6 and 8, if it gets below 6 your in trouble, if it gets to the minimum of 4 you drove off the CLIFF and will need to SLAM... If you need to go higher then 8 FC to maintain above 6 FC that is fine..

 

[BassPlayingDude]

Are you passing OCLT to determine when your SLAM is complete? You may be ending your SLAM s too early and thus leaving some level of organics behind. SLAM until you pass OCLT and then add one more day for good measure. Also, brush lights, ladders etc where algae can hide. Some species of algae form a biofilm and brushing is necessary to make sure they are exposed to the chlorine. One good SLAM and maintain when I open is all I've ever needed. I did one additional SLAM last year just to be on the safe side when my son gagged and barfed in the pool after getting a mouthful while diving.

 

[bmj0928]

I have done 2 SLAMS in 8 years... Think of the minimum as a CLIFF, you NEVER want to drive off a CLIFF...

For a CYA of 50 you want to keep you FC level between 6 and 8, if it gets below 6 your in trouble, if it gets to the minimum of 4 you drove off the CLIFF and will need to SLAM... If you need to go higher then 8 FC to maintain above 6 FC that is fine..

I think you convinced me to do a partial drain and refill...

 

[Donldson]

I think you convinced me to do a partial drain and refill...

Having a lower CYA could make it worse. Lower CYA means more burnoff from the sun. Makes it a lot easier to drop below the minimum and get a bloom. Nothing wrong with keeping the FC high, it's just getting over the mental block of "swimming above 3 ppm FC is dangerous" propaganda we've been fed since first owning a pool.

To answer your initial question: Once when I open but because I close and open when the water is about 50 degrees it's pretty quick. Occasionally if I go away for more than a week I drop below the minimum and do a preventative one just to be sure.

 

[HeyEng]

Does anyone else have to perform multiple SLAM's a season?

It seems like I am constantly slamming my pool. If I let the chlorine drop below recommended even for a day, I seem to get a cloudy pool. I have scrubbed everything down, tried to find the hiding places, and even got new filter cartridges. I added enough LC this morning to expect an 15ppm rise, but ended up seeing a 22ppm rise. The pool is looking clearer, now, but usually the "effects of adding" calculator is dead on. My CYA is 50, but I may try to do a drain and refill to get it down to 30 or 40.

This is your main problem. You really need to maintain the level EVERY SINGLE DAY....NO EXCEPTIONS.

A drain and refill would be much more work than is needed at this point.

If you lower your CYA, you are going to use more chlorine.

I would recommend a review of Pool School to get you back on track.

 

[DeanP66]

You don't need a partial drain. CYA of 50 is perfectly fine and if your weather is hot during the summer, it is preferred over 30 or 40 because it will protect your FC longer from the sun. You just need to dose to 8ppm and like someone previously said, don't ever let it get below 4.

 

[bmj0928]

Are you passing OCLT to determine when your SLAM is complete? You may be ending your SLAM s too early and thus leaving some level of organics behind. SLAM until you pass OCLT and then add one more day for good measure. Also, brush lights, ladders etc where algae can hide. Some species of algae form a biofilm and brushing is necessary to make sure they are exposed to the chlorine. One good SLAM and maintain when I open is all I've ever needed. I did one additional SLAM last year just to be on the safe side when my son gagged and barfed in the pool after getting a mouthful while diving.

I found a post that had a chart for "mustard algae" SLAM levels, and have used that. Earlier this year I had a very successful SLAM, and have been able to maintain... until now. I suspect I have a mustard algae problem lurking somewhere, and wonder if the mustard algae is in the return pipes that I can't reach with brush. The first indication there is a problem is that my stairs turn yellow (where the returns are) and the white skimmer turns yellowish in the corners. It almost looks like an iron issue, but it clears up with the SLAM and brushing. It also rubs off with my hand or a scotch brite pad.

Over the past few weeks we had a ton of rain, here in Pittsburgh, and I neglected adding chlorine for a few days. That was a mistake, apparently, because I pulled the cover back to a gross looking pool.

 

[Saturn94]

I do a quick SLAM at opening. At closing, I bring it up to SLAM level just before covering it for the winter. I never have to SLAM during the season.

 

[Donldson]

Nothing you described sounds like mustard algae. Also there's a specific process for mustard algae, not just performing the SLAM Process with high FC.

 

[bmj0928]

Nothing you described sounds like mustard algae. Also there's a specific process for mustard algae, not just performing the SLAM Process with high FC.

I feel like such an amateur.

It is curious, though, that this yellow/orange stuff clears with high chlorine, and appears when it drops (and the pool clouds up). It doesn't come up with a brushing or vacuuming, but does when I rub it with my hand. It also seems to happen in areas with higher water movement: skimmer, and stairs where the returns are...

 

[BassPlayingDude]

We all started this as beginners . Every pool is different, and it takes a few seasons to fully grasp what works for yours.

 

[BassPlayingDude]

One year I had some scunge in my skimmer. I got one of those plastic spray bottles and ( while wearing safety goggles!!! ) sprayed the area thoroughly with full strength 12.5% shock. Maybe that might work for you.

 

[Donldson]

Not entirely sure what it sounds like, though in spite of some odd behavior iron would still be my first guess. It definitely doesn't sound like mustard algae, or really any common algae. Mustard algae forms in shadows, generally where there's not a lot of high water flow, and puffs up at the slightest touch.

Next time it happens try holding a vitamin C tablet against it to see if that causes it to fade. If that doesn't work, if you have a chlorine tab you can hold that against it. If the C makes it fade then it is iron, if the tablet makes it fade then it's organic. If neither works then we dig deeper.