I added polyquat to my pool several weeks ago before closing and it surprisingly dropped FC to below minimum FC level for my CYA. This concerns me because its been warm since closing so FC might be at zero by now. When I expressed my concerns about this FC drop to my experienced pool guy, he recommended that I add some more algaecide to my water in the late winter to ward off algae, since the rain water will likely lower the chlorine and algaecide over the winter. He claims that adding algaecide 60 to a closed pool would be safer than adding liquid chlorine because it is non-staining and won't leave a bleached out spot where it is added like liquid chlorine would. He recommended dissolving it in a bucket of water and pouring it into the pool. Has anyone tried this before, did it cause any staining, and does it help ward off algae better than chlorine would? I added polyquat at closing last year and our water was green by early March so I'd be willing to try this if it might help and wouldn't cause any staining.
Adding polyquat 60 to a closed mesh-covered pool
- Thread starter ba67
- Start date
- Jun 7, 2017
- 9,990
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
You can peel back the cover and drop in a submersible pump and then add the liquid chlorine and even use the pool brush. Perhaps move the pump around to push water different directions then take a water sample to see what you have. I'd consider this method rather safe.
I was talking about adding polyquat instead of adding liquid chlorine. I thought that you weren't supposed to add liquid chlorine if you closed with polyquat because the liquid chlorine would degrade the polyquat. If I added chlorine instead, wouldn't the polyquat just consume it like it did when I added it at closing? If adding polyquat in a few months would potentially help ward off algae and wouldn't stain my pool, I'd be willing to try adding some with a submersible pump. I plan on opening when the threat of freezing overnight temperatures has passed in late March/early April, but I worry that all of the warm days in late winter will trigger an algae bloom before it is opened if there isn't any chlorine or polyquat in the water.
It looks like the water temperature is finally down to 60 degrees, even though we've had a lot of warm days since closing. Water temperature was 65 degrees at closing.
- Jun 7, 2017
- 9,990
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
Water temp is key. Close when it is below ~60 and open when it is above ~60. A few warm days aren't going to push you over the edge unless your water only gets to low 60s.
Since the water temperature was 65 degrees at closing and we had a week of warm weather in the 70s/lower 80s after closing, I worry that the FC is already at 1 ppm or 0 now since it was below minimum FC after adding the polyquat before closing. I just wanted to know if adding polyquat with a submersible pump in a few months to ward off algae might help and if it could cause any staining or other problems. I could add liquid chlorine instead if it can be added without degrading the polyquat and the polyquat that was already added won't consume the chlorine.
- Jun 7, 2017
- 9,990
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
Chlorine will oxidize polyquat, rendering it less effective or even useless. 65 is borderline needing chlorine. If you are getting warm days and sun on the pool, I suggest keeping it chlorinated as long as conditions dictate. I would choose chlorine over polyquat.
A little off the subject but this thread is a great example of the issues with polyquat.
I am not particularly a fan and believe SLAM value chlorine at closing is virtually as effective
I am not particularly a fan and believe SLAM value chlorine at closing is virtually as effective
+1 to both above. To me, PQ is a Hail Mary and there's no way to test to know if you're prayers will be answered.
I know that chlorine will oxidize polyquat so I know that it wouldn't be wise to add any chlorine now. I was asking if it would potentially help if I added some more polyquat in a few months while draining water out since I know that the rain will dilute the polyquat and what little chlorine is left in the water. My pool guy says that I can add polyquat even though the pump isn't running and it won't stain the pool but I wanted to check on here to see if this is correct since I know everyone on here is a lot more knowledgable about chemicals than my pool guy.
After this experience, I think I will skip the polyquat next year. I've used it for 5 years and it never lowered the chlorine that much. It normally only lowers the FC about 3 PPMs but this year, it lowered it down to minimum FC level. The fact that it got so hot after closing worries me because the FC could be close to 0 by now. Just wanted to see if adding some more polyquat later this winter could potentially help ward off algae since I know that I'm not supposed to add any chlorine because of the polyquat in the water.
Welp. Adding either OQ or LC mid winter will leave you with more than you started with at that point in the off season, even after they interact.
By that time, it'll be cold enough you don't need either, and either is really just pre-dosing for the early spring. Then open soon after the last freeze and you're good to go.