So for about 3 weeks I have been fighting what I think is dead algae that settles to the bottom of the pool, I've been thinking that this is dead algae (from a previous bloom). Almost daily I have been vacuuming it to waste and backwashing, looks great after the vacuuming...........until the next day, so I vacuum again and this cycle keeps repeating. Brief description of what I am vacuuming: dusty sandy looking debris that settles in low spots of the liner or low flow areas. It is light brown maybe a little grayish (almost the color of cardboard) the particles are much smaller than sand, you can not pick it up and if you wave the pool brush brush over it without touching it, it disappears. Starting thinking this was only in my filter and was being put in while pump and filter is in operation so I turned my pump off for 24 hrs and the pool floor stayed spotless. Could there be this much dead algae in my pool filter? Could the algae be live and dying off daily and settling? Could it be something totally different. Any help would be appreciated. I am a first time poster and only have limited pool experience........please be patient with me until I learn the ropes. Thank you all in advance.
Possible dead algae from sand filter being put into pool and settling in low spots or low flow areas.
- Thread starter JLP3
- Start date
- Jun 22, 2014
- 52,018
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Welcome to TFP! 
It does sound like algae. Can you post a full set of water test results and tell us how you chlorinate on a daily basis? Also be sure to update your signature with all of your pool and equipment info. See mine as an example.
Also see ------------- > Pool Care Basics
It does sound like algae. Can you post a full set of water test results and tell us how you chlorinate on a daily basis? Also be sure to update your signature with all of your pool and equipment info. See mine as an example.Also see ------------- > Pool Care Basics
Sure... Alk 80, ph 7.3, Fc 2.5, cc 0.5, cya 60, cal hardness 100. I use liquid chlorine and maintain level of 1 -4 daily
Also, when you say it does sound like algae......are you talking live or dead? Thanks
- Jun 22, 2014
- 52,018
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
I suspect that's your problem. An FC of 1-4 may sound good by the pool store, but we've learned to follow the FC/CYA Levels. Go to that link and select liquid chlorine pool with a CYA of 60. You'll see teh ideal range and the absolute minimum to prevent algae. Your FC is much too low. I suspect you have live algae growing. If you have doubts, you can do an Overnight Chlorine Loss Test to confirm.
I suspect a SLAM Process will be next.
I have these too, although I have a cartridge filter.
If it is algae, then 1. You will have overnight chlorine loss; 2. When on slam level, these things should not return.
In my case, even when I am on SLAM and passing OCLT, they still reappear next day at the exact same spot. Mine are on pool steps, so I can touch them. They are very fine particles. But if I rub them against skin, it will feel rough. I don’t think if I rub dead/live algae against skin, one’d feel anything. (Knock on wood that mine are indeed just sand… really don’t want to go through another SLAM.)
If it is algae, then 1. You will have overnight chlorine loss; 2. When on slam level, these things should not return.
In my case, even when I am on SLAM and passing OCLT, they still reappear next day at the exact same spot. Mine are on pool steps, so I can touch them. They are very fine particles. But if I rub them against skin, it will feel rough. I don’t think if I rub dead/live algae against skin, one’d feel anything. (Knock on wood that mine are indeed just sand… really don’t want to go through another SLAM.)
I am actually on day 2 of the slam. The test levels I posted was taken just before I started the slam. I vacuumed everything to waste, brushed everything twice, re-vacuumed to waste, backwashed and rinsed the sand filter, put pump in continuous operation and started. I raised the free chlorine level to 24 and started maintaining the level. I am still getting the stuff settling on the bottom, I just keep vacuuming to waste and maintaining fc level. My combined chlorine level is 0 and the pool is crystal clear except for what is settling to the bottom. I'm gonna keep brushing and vacuuming tomorrow while maintaining fc level. I will probably do the oclt test tomorrow night. So here is where I am confused and maybe someone can speak to this. If this is algae that is settling as it dies, how could it be still alive and actively dying and settling when the fc has been at 24 for 2 days. I don't get it...I'm just frustrated been dealing with it for going on 3 weeks. Is it possible that all along its been dead spores trapped in sand filter and just keeps making its way out into the pool and falling to the bottom? THANKS GUYS.