Day 21 of SLAM & is this possibly algae??

[Burntwoods]

Hi all -

We are coming up to day 21 of our SLAM. We've been pretty good at keeping the FC in the 10-12 ppm range. A few times it went down to 6 or 8, but that was only 2 or 3 times when we were away for > 24 hrs. Our CYA is at 20, and the CC usually tests at 1.0.

What the pool looked like when we started out:
https://www.troublefreepool.com/threads/161129-Ready-to-SLAM-must-we-fully-increase-CYA-first

We've been trying to brush the sides daily, and have gotten it done most days.

Just today I noticed that I can (kind of) see the third step in the shallow end. That's the best visibility we've had, but of course that's many feet away from seeing the bottom of the deep end.

We didn't have a vacuum for the first 10 days, so we could only blindly scoop out the bottom (and there was LOTS of debris/muck down there.) Since we have gotten one, we've tried to vacuum every few days. We're still seeing muck, leaves, etc, come up, so there is still stuff at the bottom of the deep end.

In the past week and a half or so, we've noticed what we thought was sand in our cartridge filter. Initially we thought we were vacuuming it up, but realized that it's there even when we haven't vacuumed in between filter cleanings!! Is it possible that this is algae remnants?? (it feels a little softer than beach sand, more 'gunky' and less gritty.) It's on the top as shown in the image, as well as about 3" deep at the bottom of the unit (we use the shop vac to remove it when we clean the cartridges.)

Appreciate any advice or input to keep us moving towards a trouble free pool.
Thanks!
Matt

 

[aussieta]

my thoughts are there is still a lot of cdebris in the pool
your not going to win until you get it all out

 

[HiddenRiver]

Can you post a full set of water chemistry test results? Do you have a good test kit like the TF -100? 21 Days is too long it seems so I would agree if you haven’t removed Plant debris and other solid material you may not win the battle. Also, looks like your CYA is too low. Hopefully one of the experts will chime in soon but I know they will want to see all your test results before providing advice. Free Chlorine, Combined Chlorine, pH, Total Alkalinity, Total Hardness and CYA—

 

[Texas Splash]

Re: Day 21 of SLAM & is this possibly algae??

Yeah Matt, I'm afraid this battle will go on for a while until you can really scour that bottom really well. There's no doubt that chlorine will clear water, but it can't do all the work to breakdown solid matter - at least not quickly. On top of that, if your CYA was ~ 20, we know that's low which would explain additional FC loss. What I would do at this point, or probably starting tomorrow when you can see in the light outside, is if the FC is below 10, check your pH again. It may have been a while since you last tested. Make sure the pH is about 7.2. Once confirmed, validate your CYA and make sure you have at least a CYA of 30. At that point, keep the FC at 12. From that point forward, or this weekend, your #1 goal is to remove all the dirt, leaves, and any other muck that settled to the bottom. Guaranteed it won't be easy or pretty, but that's what needs to happen. Trade of with a helper or do it together with a rake, brush, vacuum …. all of the above. But you have to remove that junk down there. At that point, your bleach will have a much greater impact on the water and you'll begin to see visible improvements.

- - - Updated - - -

At the same time, keep an eye on your filter (pressure). The more stuff you kick-up from the bottom, the more that will get to the filter and make it look like the pic above. You'll need to rinse those cartridges often I'm afraid, but at least you're getting it out.