Floc or not for overnight clear up?

tomfrh

Well-known member
Jan 30, 2018
484
Australia
My filter let some dirt into the pool. It had channeled I think. I’ve cleaned the filter and it’s ok again now, but the pool is a bit cloudy.

I want it clearer for tomorrow (Christmas)

Should I floc and vac to waste in the morning? Or instead run filter overnight?
It’s now 5pm. I’d floc it around 9pm, and vac 12 hrs later.

ive used floc before, but not since TFP, as I know a filter can clear water.Problem here is the lack of time!
 

aussieta

Gold Supporter
TFP Guide
are you planning on swimming or just want it to look tfp clear for visitors
will you have time to vac to waste, top up water and adjust chemicals with young children and christmas or getting ready for guests
i think i would just run filter overnight
 
  • Like
Reactions: CRAD_oz

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
22,131
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
How dirty is the water? Can you see the deep end?

Why can’t you swim in the water while waiting to let the filter clear the dirt?


TFP discourages the use of flocculants with ALL filter medium.

Flocculant is a glue that causes particles in the pool water to clump together and fall to the bottom of the pool. Flocculent does not get rid of live algae, or lower CH, or remove CYA from the water.

Flocculants should only be used if you can vacuum to waste. Vacuuming flocculant into a filter can gum up the filter, require major cleaning of a sand filter or DE filter, and destroy a cartridge.

The circumstances where floc actually fixes something that won't fix itself with a little patience are extremely rare. If it works perfectly it shortens the clearing time slightly. If it fails, you can be dealing with huge consequences in both time and money. Not to mention it can mask ongoing issues that otherwise would have been properly fixed.

Flocculant is almost never entirely removed from the water after vacuuming to waste and causes cartridges to become almost useless. Sand filters can more readily recover from a proper floc treatment, but long-term it will ruin those too.

One of the few times TFP recommended the use of a flocculent was to clear a pool of ashes from a wildfire. We advise to exhaust every other possibility before using a flocculant. Floc's and clarifiers can be tricky to use and, if used incorrectly, they can cause a royal mess. So they are definitely a method of last resort.

Flocculent is different then a clarifier. Clarifiers will cause small particles to clump together so they can be skimmed out and captured by the filter. Flocculents cause larger particles to glue together and fall to the pool floor. Flocculents need to be vacuumed to waste and never to the filter.

If you have already added flocculent to your pool and let it into your filter:
  • for a sand filter, there is a great chance you will need to change your sand
  • Cartridges need to be replaced in a cartridge filter
  • DE filters need to opened and the grids cleaned.
 
Last edited:
  • Like
Reactions: CRAD_oz

tomfrh

Well-known member
Jan 30, 2018
484
Australia
The floc worked out ok. It cleared up enough for me to vacuum and use the pool on Christmas Day.


A little more floc has precipitated out now (Boxing Day) and the pool is very clear.
If I ever floc again I’ll leave it for longer to start with.