I am currently performing a SLAM and believe I may almost be done. I tested my FC at 10:30pm. How early in the morning can I test my FC to complete the Chlorine Loss Test?
How early can I test for an Overnight Chlorine Loss Test?
- Thread starter frankytii
- Start date
- May 3, 2014
- 58,311
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
I suggest you slam for an extra day to be certain you're done and then do the OCLT along with all 3 criteria.
johnnyleo11
Well-known member
I do it earlier in the morning so the sun doesn't have the chance to eat up any chlorine.
Failed the OCLT. Water has been crystal clear and has a CC of 0.5ppm, but I lost 3ppm of FC during the OCLT. I’ll be going on day 11 of the SLAM. Started because I had a CC of 1.5ppm. I’ve been brushing and vacuuming every day too. Filter pressure has been good. Is there a need to backwash during a SLAM if the filter pressure hasn’t increased?
Attachments
- May 3, 2014
- 58,311
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Backwash your filter when your filter pressure rises by 25% over clean filter pressure.
Stay at the SLAM. Check all possible hiding places for algae, Light niche, skimmer throat, weir door, etc.
Stay at the SLAM. Check all possible hiding places for algae, Light niche, skimmer throat, weir door, etc.
Will do. Should I unscrew the light and clean behind it? I’ve never removed it before.
- May 3, 2014
- 58,311
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Does your light have a metal ring around it? If so, check for a single screw near the top. Remove that screw, the ring should swing down, and the light assembly brought to the surface on the deck. Then clean the niche. Be ready -----
It has a white plastic ring with a single screw on top. I’ll do that. Is it likely to be pretty nasty behind there?
Attachments
- May 3, 2014
- 58,311
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
The answer is maybe and that's final. The light is a good place to start.
Think I may have found my FC demand issue?
Not saying conclusively BUT.... I've been chasing a FC demand issue that maintaining shock levels for days wasn't taming. Have been losing about 6ppm FC per night while trying to achieve the OCLT. Pool is sparkling as if there is almost no water in it. No CC or less than .5. Still consuming...
www.troublefreepool.com
Then there's the skimmer
One more place to look for algae.
Just when you think you looked everywhere, BAM, the weir door foam. Never imagined i had to look there. Never had dull water just FC loss of 4-5ppm with cool weather and low UV index. Started cleaning the skimmer for a complete brushing and found this. I would recommend finding a higher density...
www.troublefreepool.com
And I can't find the thread, but within the last couple weeks someone struggled with finishing a slam on a crystal clear pool and it was some kind of slime on his cartridge filter. A good cleaning and he passed.
Thank you. The photos from that light niche thread were shocking. I’ll start there. I’ve scrubbed the inside of skimmer already and I don’t have a weir door.The answer is maybe and that's final. The light is a good place to start.
Think I may have found my FC demand issue?
Not saying conclusively BUT.... I've been chasing a FC demand issue that maintaining shock levels for days wasn't taming. Have been losing about 6ppm FC per night while trying to achieve the OCLT. Pool is sparkling as if there is almost no water in it. No CC or less than .5. Still consuming...
Then there's the skimmer
One more place to look for algae.
Just when you think you looked everywhere, BAM, the weir door foam. Never imagined i had to look there. Never had dull water just FC loss of 4-5ppm with cool weather and low UV index. Started cleaning the skimmer for a complete brushing and found this. I would recommend finding a higher density...
And I can't find the thread, but within the last couple weeks someone struggled with finishing a slam on a crystal clear pool and it was some kind of slime on his cartridge filter. A good cleaning and he passed.
- Mar 5, 2020
- 2,965
- Pool Size
- 66000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Astral Viron V35
Another place where I once found algae is in the connections of the individual segments of the pool hose. If you have a suction side cleaner that is permanently in the water and the hose is not fully submerged, then algae can get a hold in there. If you have one of those segmented hoses, then it's worth taking that apart, and give the connections a good brush and soak in your SLAM level water.
- May 3, 2014
- 58,311
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Thanks for your help! If this is the only place where I had algae and I scrub it all off, how much longer of performing the SLAM will I likely have?
- May 3, 2014
- 58,311
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
Hard to say. May be done tonight. Leave the light out of the niche over night. Also, if you can hang the light into the water so it is fully immersed in the SLAM level FC water too.
Any tips on keeping the light immersed in water? Mine floats at the top.
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