Stubborn Algae

Texas Splash · Dec 30, 2017

Sounds like you are heading in the right direction. Stain removal can be a slow process, but any progress is good. Mustard Algae (MA) is an elevated level used primarily to treat MA that can be very stubborn, but it's only used in confirmed cases and only for 24 hrs "after" a standard SLAM has been completed. You can view the suggested MA level near the bottom of the Poolmath Calculator next to "Suggested FC Levels". So once you pass the 3 SLAM criteria, it's an option to consider giving those spots an addition punch, but only for 1 day. After that, maintaining your FC at the higher end of your recommended target zone, along with consistent scrubbing, may just take a while to ultimately get those spots to fade away. Organic stains can take a while. Good to hear you got your replacement kit. :goodjob:

I need to order mine soon. :wink:

cfherrman · Dec 31, 2017

Siber Express said:
Although I am in the Minority here and no matter what I say it is not going to change anyone else's mind. Get a phosphate test kit or have your local pool store test it for Phosphates. Treating the problem is needed, since obviously treating the symptoms isn't.
You can tell the guy who wants to loose weight to walk a mile a day. But not changing his diet it is going to take a long time

This is so funny, the problem is fc/cya, not phosphates! Treating for phosphates is more like treating a symptom.

Can a mod separate these phosphates post into it's own thread as it is a huge hijack

Dave2590 · Jan 1, 2018

Texas Splash said:
Sounds like you are heading in the right direction. Stain removal can be a slow process, but any progress is good. Mustard Algae (MA) is an elevated level used primarily to treat MA that can be very stubborn, but it's only used in confirmed cases and only for 24 hrs "after" a standard SLAM has been completed. You can view the suggested MA level near the bottom of the Poolmath Calculator next to "Suggested FC Levels". So once you pass the 3 SLAM criteria, it's an option to consider giving those spots an addition punch, but only for 1 day. After that, maintaining your FC at the higher end of your recommended target zone, along with consistent scrubbing, may just take a while to ultimately get those spots to fade away. Organic stains can take a while. Good to hear you got your replacement kit. I need to order mine soon.

Hi Pat, Got busy yesterday (NFL) and didn't have time to tend to the pool. Tested this morning and FC dropped to 9. Added 3/4 gallon of chlorine to bring it up. CYA about 25 so added a small amount of stabilizer. Vacuumed the algae and put the solar cover on as its windy and cold here. Wife said there was no algae in the pool yesterday but there was this morning. In the old days when I had my inground gunite pool in Erie, Pa I would just put some shock in and forget about it. Hmm, the good old days?

Texas Splash · Jan 1, 2018

Yes, the good old days. Of course we're all learning new tricks of the trade to keep our pools crystal clear. Now that we have 6 days until wildcard games, you can focus on the SLAM again. :grin: Maintain the FC at 12 as best as you can, and as best as weather and schedule permits, scrub those surfaces. Algae can be stubborn and create a biofilm that requires manual break-up for the chlorine to penetrate it. Continue this until you pass all 3 SLAM criteria. Once you do pass the SLAM, we'll look back and see if anything else (i.e. black spots) still requires attention. Have a great New Year's Day.

Dave2590 · Jan 10, 2018

Just a quick update to let everyone know I still have the black marks on the bottom of my vinyl pool. Now that its warmer outside I am vacuuming every day and adding 1/2 gallon of bleach. I have been fighting this for weeks if not months and getting tired. Water got pretty cold with the cold weather here, below 60. The spots are not as pervasive so it looks like I might be making progress. I haven't checked the exact FC reading but I'm sure its pretty high, most likely higher than necessary but I'm losing patience.

Texas Splash · Jan 10, 2018

Hi Dave!

Still adding 1/2 gal everyday? Humm. That seems like a lot right now with chilly water. My pool is a little larger and I add a half gal maybe every 3-4 days. Sounds like something is still in the water eating that chlorine. Did you ever complete the SLAM by passing all 3 criteria? I don't recall, but have you inspected the solar blanket (if being used) for any algae?

Dave2590 · Jan 11, 2018

Hey Pat, Pretty sure that something is still in the water. By adding the half gallon a day I'm trying to make sure I keep ahead of it even if I error on the side of a little too much chlorine. I have not checked to see if I pass all 3 criteria because I am still seeing the black spots daily but far fewer. I vacuum every day. I do have a solar blanket. I haven't been using it much since I need ready access to the pool and its not easy to roll up the cover. I didn't notice any algae the last time I rolled it up. Not to mention as cold as its been the cover would not help much anyway.