Pool SLAM advice needed

[jessman1128]

Our pool water was just about black due to it not being winterized or covered correctly over the winter. I started attacking it on Monday after finally finishing the upgrade of my pool plumbing. Numbers/additions so far are listed below. I've seen some definite improvement in the water so far - it's now a mild brown color, and I can see maybe 6-8 inches down from the top before it's too murky - previously it was murky all the way to the top. Wondering if I'm generally on the right track and just need to keep up the attack, or if I need to modify my approach somewhere.

6/25 9:00am - pH 7.1, TA 150, CH 350, FC 0, CYA 0
-Added 18 oz of 6% bleach and 43 oz of 12.5% bleach (both old bottles from last year - which likely contributed to the very low FC reading 3 hrs later - probably much less than 6% and 12.5% after sitting that long)

6/25 12:15pm - FC 1.0
-Added 32 oz of 6% bleach and 32 oz of 12.5% bleach (I think these were from last year's bottles too, but don't recall for sure now)

6/25 6:35pm - FC 0.5, CC 2.0
-Hmm, just realized I missed logging the addition at this time - was likely ~44 oz of 12.5% bleach (new bottles from here on out)

6/26 12:30am - FC 2.5, CC 1.0
-Added 40 oz of 12.5% bleach

6/26 10:15am - FC 2.0, CC 3.0
-Added 44 oz of 12.5% bleach

6/26 9:20pm - FC 0.5, CC 1.5
-Added 52 oz of 12.5% bleach

6/27 7:40am - FC 0.5, CC 1.0
-Added 52 oz of 12.5% bleach

I didn't have any CYA in the pool until yesterday - I added what I had left from last year in a sock in front of the return, and it was pretty well dispersed by this morning. I need to get more today to get the level up to a readable amount. It's also been hot and mostly sunny every day this week which I know is eating up chlorine as well.

I've been targeting raising FC to 10 each time, and wondering if I should be going higher. Also whether the lack of CYA is going to hurt my efforts to get the water cleaned up, and if so, how much of a factor will that be? Thanks for any advice you can offer! We went on vacation last fall for a week with the pool uncovered and I never got it cleaned up when we got home, despite trying to SLAM it for a week or two. Really hoping to get a better result this time around. Feel like I must be missing something somewhere.

 

[mknauss]

Please read through the SLAM Process. It is necessary to have 30 ppm of CYA in the water to complete a SLAM. With 0 CYA, the sun is burning off your chlorine in minutes.

 

[Richard320]

You have three things competing for your bleach: sunlight, algae, and organics. Getting CYA to 30 will help with the sun. Scooping any leaves and vacuuming blind will get rid of organics. Then the bleach can work on the algae.

 

[aeh0603]

It could just be the algae consuming most of your FC between tests, but since you say your CYA went to 0, have you done an ammonia test? There is a bacteria that can eat CYA and turn it in to ammonia.

To do the ammonia test:
1) Add enough bleach to reach 10FC
2) Wait 10-15 minutes and test FC and CC

• If FC is higher than 5 you pass the test and do not have ammonia. Continue with normal SLAM procedure.
• If FC is lower than 5 and CC is high, you likely have ammonia. Go to step 3.

3) Continue checking FC and dosing bleach to reach 10 FC every 10-15 minutes until FC holds above 5. Do not add more CYA until this occurs. Ammonia consumes FC almost instantly, so it's important to have a lot of bleach on hand if you have ammonia and keep dosing every 10-15 minutes until the FC holds above 5. At this point you beat the ammonia and you can continue with the normal SLAM procedure.

 

[jessman1128]

Thank you, @mknauss, @Richard320, and @aeh0603!! I got some more CYA and have the level up to somewhere between 30 and 60 now. I'm struggling with proper reading of the CYA test. I've been adding chlorine as if CYA was 35 as that's mostly the result I was getting based on how I was reading the test. After reading through some more details/suggestions on that test this afternoon, I suspect I've been doing it not quite right and the actual level is even higher, but haven't had a chance to repeat the test since then. So with assumed CYA of 35 I've been adding 12.5% bleach to raise FC to 14 each time. It is staying around for a lot longer now with the CYA levels up. The water finally cleared up "enough" for me to kind of see the bottom of the pool and I discovered quite a few dark patches on the pool floor. Decided it was high time to figure out how to vacuum the pool - took a bit for me to get it figured out, but the addition of the Hayward skimmer has certainly simplified what would have otherwise been much more difficult, I think. I've figured out the vacuum process and have started sucking up all the leaves on the pool floor, but I can only vacuum for maybe 1-2 minutes before the pool filter gets so clogged the pump can't pull anything through it. So then I have to take the filter out and hose it down and having to do that so frequently really slows down the overall vacuuming of the floor. Which brings me to my first question:
-Any reason why it would be ill-advised for me to disconnect my return hose, remove the filter from the filter housing, and vacuum that way with pushing everything out into my yard via the return hose? I know I'll lose a lot of water in the process but I think that'd be preferable - and faster - if it gets me around having to clean the filter every few minutes. There's still a LOT of leaves on the pool floor and if I continue the way I have been it'll likely take me at least 2-3 more evenings to get them all cleaned up. (Clarification: it's not the large leaves that are clogging the filter, it's all the tiny pieces of material from all the leaves that have broken down over the last 6 months - I suspect I can get a lot of those pushed out during the vacuuming too though with the method I'm asking about.)

Second question:
-Should I continue with the SLAM process even while I'm still working on getting all the junk (aka leaves) out? I have been, but I'm wondering if I'm largely just wasting chlorine and if I should discontinue adding any chemicals until I get the bulk of the leaves out.

Here are some of my recent levels:
6/29 10:45am - FC 3.0, CC 1.0, CYA 35
-Added 56 oz of 12.5% bleach

6/29 1:00pm - FC 14.0, CC 1.0
-No additions

6/29 4-6pm - first session of the vacuum/clean filter cycle

6/29 5:45pm - FC 7.5, CC 0.5
-Added 34 oz of 12.5% bleach

6/29 10:15pm - FC 10.5, CC 1.0
-Added 12 oz of 12.5% bleach

6/30 7:15am - FC 10.5, CC 1.0
-Added 18 oz of 12.5% bleach

6/30 1:15pm - FC 10.5, CC 1.0
-Added 18 oz of 12.5% bleach

6/30 4pm - second session of the vacuum/clean filter cycle

6/30 9:20pm - FC 9.5, CC 1.5
-Added 22 oz of 12.5% bleach

 

[mknauss]

With an above ground pool you can use a siphon to vac with. Install the vac, start the pump. Get good flow. Turn off the pump. Remove the suction side line, and water should pour out. Then use the vac to remove the solids. You will lose water pretty quickly.

Keep adding chlorine.

Get a good CYA after you do the vac to waste process. You need it to know your SLAM level FC.

 

[IceShadow]

To clarify - don't just run the water through your pump without baskets. Junk can get into your impeller and plug it up. mknauss above is advising a way to get the vacuum to work without having water go through the pump.

 

[jessman1128]

I'm fairly famous in my family for not seeing the forest for the trees - having tunnel vision, basically. After lamenting to my wife Monday about the slow progress with the vacuuming she asked why I didn't just use the long-pole skimmer to scoop up as much of the debris as possible from the bottom and lift it out. That has worked quite well, with only a fraction of the water loss that siphoning would have provided. It did, however, stir up the stuff on the bottom and the pool fairly quickly turned to a green/gray color and has stayed that way for two days now. I wasn't able to see the bottom last night but I used the skimmer to feel along the bottom and found a fair amount more of leaves/debris to lift out. Hard to say for sure how much debris is left since I can't see the bottom but I think I've probably got 75-90% of it out. There's bound to be some in the center where I can't reach with the pole.

I repeated the CYA test last night and this morning. Last night was cloudy and I just couldn't get a good read that I was satisfied with, despite multiple attempts. I was able to repeat it this morning in the morning sun and I'm fairly confident that I'm at 55 for CYA. Still not totally confident but I think I'm starting to notice the difference between actually seeing the black dot vs seeing a shadow/reflection that looks similar to the black dot.

I added chlorine last night as if CYA was 60, but the visual appearance of the pool didn't change at all overnight. Not sure if it should have or not.

I added chlorine this morning for the CYA of 55 (which translates to SLAM level of 22). Recent tests/additions below. Just wondering where to go from here. I have to hose down the filter quite frequently. It gets clogged up somewhat with little pieces of vegetation, and clogged up very much with the green-ness of the water. The white pleats are completely covered in the green goo that has to be completely hosed off. Do I just need to keep SLAMing for however many days this takes or is there some way to speed this up or something I'm not doing correctly?

7/1 8:30am - FC 8.5, CC 1.0
-was in a rush and didn't add any chlorine :-(

7/1 7:15pm - FC 3.5, CC 1.0
-Added 54 oz of 12.5% bleach

7/2 7:00am - FC 9.5, CC 1.0, pH 7.2
-Added 56 oz of 12.5% bleach

7/2 8:15pm - FC 11.5, CC 1.0
-Added 60 oz of 12.5% bleach

7/3 8:30am - FC 19.0, CC 1.0
-Added 16 oz of 12.5% bleach

Pics from this morning:

 

[mknauss]

Is a drain and refill an option? Sometimes it is best to start over.

You may have to leave 1 foot of water in the pool to keep the liner from shifting.

 

[jessman1128]

Is a drain and refill an option? Sometimes it is best to start over.

You may have to leave 1 foot of water in the pool to keep the liner from shifting.

I suppose it's possible, although I was definitely hoping to avoid that route. If I don't take that route, is it likely to take quite a few more days to get this under control?

 

[aeh0603]

7/1 8:30am - FC 8.5, CC 1.0
-was in a rush and didn't add any chlorine :-(

7/1 7:15pm - FC 3.5, CC 1.0
-Added 54 oz of 12.5% bleach
This raised your FC by 8.8 to reach 12.3

7/2 7:00am - FC 9.5, CC 1.0, pH 7.2
-Added 56 oz of 12.5% bleach
This raised your FC by 9.1 to reach 18.6

7/2 8:15pm - FC 11.5, CC 1.0
-Added 60 oz of 12.5% bleach
This raised your FC by 9.8 to reach 21.3

7/3 8:30am - FC 19.0, CC 1.0
-Added 16 oz of 12.5% bleach
This raised your FC by 2.6 to reach 21.6

All that scooping of debris with the net is definitely going to help speed things up! Great job! I do see one area for improvement though. You stated that your SLAM target is 22, but it doesn't look like you are adding enough chlorine to actually reach that target. This will slow down your progress. From the pictures it looks like your pool is still quite green which means you have not killed all the algae yet. The more often you can test and raise your FC to SLAM level, the faster your progress will be. You may want to review the SLAM PROCESS again and make sure you are following all the steps (brush at least once a day and clean your filter when pressure rises 25% above clean pressure).

Also, TFP generally rounds up to the nearest 10 for CYA value. The scale is logarithmic not linear, so you can't accurately estimate CYA value between lines on the tube. This means you should round up and call your CYA 60 and use a SLAM target of 24 FC per the FC/CYA chart.

 

[jessman1128]

Also, TFP generally rounds up to the nearest 10 for CYA value. The scale is logarithmic not linear, so you can't accurately estimate CYA value between lines on the tube. This means you should round up and call your CYA 60 and use a SLAM target of 24 FC per the FC/CYA chart.

Thank you! I didn't realize it wasn't safe to estimate between the lines. The effects you referenced for my recent additions were notably lower than what I've been getting from the "Effects of Adding" part of the app. Wasn't sure what to make of that so I decided to check if my pool volume is correct in the app. Over the past couple of weeks I've noticed it set at 5061 in the "Effects of Adding" section and figured I had calculated that last year and didn't think twice about it this year. I just checked and it looks like I should actually be using around 6000 - yikes, that would definitely make a difference in the calculations! I'll make the necessary adjustments this evening when I'm home from work and then attack it hard tomorrow when I'm off work to see if I can start making some visible headway with it. If it doesn't look any better by this weekend I'll likely go the drain-and-refill route.

 

[mknauss]

I suppose it's possible, although I was definitely hoping to avoid that route. If I don't take that route, is it likely to take quite a few more days to get this under control?

That is correct. All about your timing. With that amount of organics (you are still unsure if there are solids on the bottom) and if you have a sand filter (you do not show what filter you have in your signature), the SLAM Process could easily take a couple weeks.

 

[jessman1128]

That is correct. All about your timing. With that amount of organics (you are still unsure if there are solids on the bottom) and if you have a sand filter (you do not show what filter you have in your signature), the SLAM Process could easily take a couple weeks.

It's not a sand filter. Just the basic pleated Intex type B cartridge filter that comes with the pump.

 

[mknauss]

Not a lot good posted about those filters. Hope you have an additional filter cartridge as you will need to be rotating them often to keep them clean.

 

[jessman1128]

Well, I worked on scooping more plant material from the pool most of the day on the 4th, hosed down the filter frequently the 4th and the 5th, and not much visible difference by the 6th. So, on the afternoon of the 7th, I started draining it. 48 hours later it's down to about 8-10 inches of water remaining. That's about where it was this morning too; not much has drained overall during the day today. It's a pretty small stream that is coming out if the drain hose now. Anyway, on to my questions. There's still a fair bit of tree material that I'm continuing to scoop out, but there's also a hefty amount of tiny green particles littering the pool floor, presumably the same algae that was making the water green when the pool was full. How do I get all of that out before refilling the pool? Or is that not very feasible and I need to refill and then rely on my pump and filter to clean it out? I'm just concerned about getting back into the same position I was in mid last week with a pool full of green material, which does stick to my filter quite well, but there's so dang much of it that it'll take a zillion filter cleanings to get it all out.

 

[aeh0603]

The SLAM Process will kill the algae, your pool pump and filter will remove it from the water. Doing a drain and refill like you have started will significantly reduce the organic load and allow the chlorine to kill the algae faster. Right now your water is still pretty green which means your algae is still alive. You have now reduced the load, so fill your pool back up with water and keep testing and adding chlorine to reach your SLAM target based on your CYA. Draining the water also reduced your CYA, so make sure to test it once your pool is full and dose to 30 if necessary.

Good luck! You can do this!

 

[IceShadow]

Draining also let you get to the bottom and ensure no more large organics are in the pool.

 

[CarolineM]

I would shop vac out that stuff. My 1st pool was an intex and I took it down every year, the shop vac worked great at getting the last of the water out.

 

[jessman1128]

Thank you everyone!!

Right now your water is still pretty green which means your algae is still alive.

Does that mean my water should lose the green hue once the algae is dead? Does dead algae turn brown? With all the chlorine I dumped in the pool prior to draining it, it never lost its green color, which has me wondering if that means it never died, or if it's possible for it to still be green even after it's dead.

Draining also let you get to the bottom and ensure no more large organics are in the pool.

True! I did discover a couple of decent-sized patches of leaves still on the bottom once the draining was mostly complete. I had gotten at least 75% of it out previously when the pool was full, but 25% of A LOT is still a fairly sizable amount!

I would shop vac out that stuff. My 1st pool was an intex and I took it down every year, the shop vac worked great at getting the last of the water out.

I'll have to remember this next time I need to drain. Thanks for the tip!

The pool is pretty much filled now; planning on adding the last few inches tonight and then getting to work on CYA and chlorine.