polyquat question

New and confused · Sep 19, 2015

The guy at the pool store said Algae Destroyer by (Nature's Way) was what we needed when we asked for polyquat algaecide. (I looked at "Pool School" thread Winterizing above ground pools.) Is this what I should use. It has poly (oxyethylene (dimethyliminio) ethylene(dimethyliminio) ethylene dichloride) 60% and other ingredients 40%.

Thanks!

Texas Splash · Sep 19, 2015

As long as it says "Poly[oxyethylene(dimethyliminio)ethylene(dimethyliminio)ethylene dichloride 60%" as the Active Ingredient, you should be fine. Remember it's best to add only after your water temp has dropped below 60 degrees, and simply serves as "insurance" if your FC does not hold well enough over the winter. The SLAM FC is your primary algae deterrent.

ned8377 · Sep 19, 2015

Texas Splash said:
As long as it says "Poly[oxyethylene(dimethyliminio)ethylene(dimethyliminio)ethylene dichloride 60%" as the Active Ingredient, you should be fine. Remember it's best to add only after your water temp has dropped below 60 degrees, and simply serves as "insurance" if your FC does not hold well enough over the winter. The SLAM FC is your primary algae deterrent.

Polyquat 60 needs to be added when water 60 or below. Would that be before or after the slam?

Divin Dave · Sep 19, 2015

For clarification, there isnt a SLAM process required for winterizing, (unless the pool needs it).
The FC is only raised to SLAM level before covering it.

I would recommend adding the polyquat after raising the FC, so as to ensure there is no way it might interfere with the FC test.

ned8377 said:
Polyquat 60 needs to be added when water 60 or below. Would that be before or after the slam?

Sparkle · Sep 19, 2015

Divin Dave said:
For clarification, there isnt a SLAM process required for winterizing, (unless the pool needs it).
The FC is only raised to SLAM level before covering it.

The FC is raised to shock level. That's what the SL in SLAM means.
This phrase is also used in other relevant places, such as the Chlorine / CYA Chart.

chem geek · Sep 20, 2015

See this post for winterizing instructions from Buckman Labs, the makers of Polyquat. You do not want very high chlorine levels with Polyquat since chlorine will oxidize it. Having a moderately higher level (say, half-SLAM level so FC/CYA ratio of 20%) is OK, but the idea is that the Polyquat should last through the winter even if the chlorine does not.

On the other hand, if you intend to have chlorine last through the winter, then raising it to a SLAM level will have it last longer, but the Polyquat may not be as good of insurance in that case.

Texas Splash · Sep 20, 2015

That's a very good point Richard. Easy to overlook. It's clear in the "In-ground instructions:

SLAM - Two or three days before closing, I bring the pool up to shock level and hold it there until FC holds overnight (which it generally does right off on the first night). Then I let the chlorine level fall about half way back to normal levels, typically another day and a half.

The Above Ground instructions say it slightly different, so I can see where that would be easy to miss:

Clean and brush pool. Bring pool water to "shock" level and maintained there for 24hrs with pump running to be sure that there are no remaining algae blooms.

Very good point to remember. Glad you clarified that.