4 week SLAM Question

That still looks like algae, but I do want you to do the OCLT I mentioned above, and definitely let that FC drop to 12. It's way too high for your CYA, and we don't want you to have liner problems. I'll be curious to see your OCLT tomorrow morning. I don't expect you'll pass based on the looks of the water, but I'm trying to rule-out some things.

In the meantime, enjoy your evening and give the TFP Deep Cleaning a Sand Filter review. It might be good to do this weekend. :)
 
Well, I went out and jumped in to double check the ladder. Started scrubbing it again and noticed the bumpers on the bottom were a bit ajar. Started rotating and then poof, off they came and a plume of algae came out. So I flushed with fresh water a hose and scrubbed, hopefully the FC of 25+ will take care of it from here.

I’ll do the OCLT this evening and see what it gives me.

Thanks Texas Splash!
 
Started rotating and then poof, off they came and a plume of algae came out.
Ah ha! :goodjob: Outstanding. Isn't it amazing? And believe it or not, all the work you've been doing was fighting that tiny little area. It doesn't take much mature algae to really effect water chemistry. Glad you found it. I'll watch for your post tomorrow morning. Have a nice evening.
 
Okay, good to know. Continuing to SLAM it is. But continue to let the FC fall. Don't add anymore bleach. Your CYA is not high enough to support that elevated FC level and I don't want you to harm your liner. An FC of "12" based on your current CYA will suffice. Later, if you discover your CYA is actually closer to 40, then you can increase FC to 16. Hopefully, finding that mess in the ladder last night will help things clear-up over the next day or so.
 
A few more things for you to consider since you opened your pool earlier this month and have been at this for a while:
- For the SLAM, ensure you are only using regular bleach; no tablets/pucks should be in use right now; you want the CYA at 30 or 40, but no need to go higher right now
- Exposing that algae in the ladder last night was a big deal. It probably slowed your progress all this time. I say that as encouragement and to not be discouraging. You simply had no idea it was in there. But now that you found it, I would hope the water will respond accordingly to the bleach.
- As I mentioned, let the FC fall to a normal SLAM level. Going to high is a waste of bleach, and when it exceeds the matching CYA level, it can harm the liner.
- I would still consider doing the sand deep clean as noted above. It could help filter-out the dead algae much better. No need to change sand, just do the deep clean.
- Continue with the brushing and backwashing each day. Hopefully you uncovered the final big bunch of live algae in that ladder. But if you have anything else that is in the water, make sure to check it - inside & out. This includes that hopefully there is no bulk items (straw, needles, leaves, etc) still at the bottom that you don't see or haven't swept-up.

We'll watch for updates and hopefully see pics of clearer water soon. Don't get discouraged. You're making progress. Have a good day.
 
Well, initially after finding the algae the water cleared up enough to see the deep end drain. I’ve kept it at shock level and haven’t seen improvement from then. it’s been 2.5 weeks since then. I’ve double checked the cracks and ladder but haven’t found anything that could keep the pool from clearing up. Any more advice? here are some pics from today.
 
When you get a chance, can you post a new CYA and FC test please? Your water seems quite murky for being in this SLAM so long. As for the filter, the previous installation did you no favors. Since everything is glued together at the multiport, you would literally have to unclamp the valve and hope you have enough slack in the pipes so you can lift it up and out of the way. I'm not very optimistic about that. Eventually, you will need to get into the filter. It's just part of having a pool. So you might start to think about a couple unions and some new PVC just so you can separate the multiport from the filter when needed.
 

Enjoying this content?

Support TFP with a donation.

Give Support
FC- 24
CC- 0
CYA - 20

I don’t know if the rain and backwashes can make the cya drop, but it was higher 2.5 weeks ago. I agree, with the time I’ve been SLAMMING the pool should be crystal clear. the bottom is free of debris and we brush daily.
 
For sure your CYA is on the low end and could use a little boost. Yes, the backwashes can lower CYA a bit. Since it's difficult to validate a CYA under 30, we know you have some. So consider only adding another 10 ppm for now. That should get you back to 30-ish and help you retain FC better throughout the day. When a SLAM seems to drag-out a little longer than expected, I always fall back to the basics (many of which you have been doing, so please excuse the repetitiveness):
- Maintaining the "proper" SLAM level consistently throughout the day
- Brushing, sweeping, and vacuuming often
- Removing any hardware that can be removed (i.e. portable ladder, lights, etc) and cleaning inside/behind them.
- Cleaning the filter; for sand it includes backwashes when psi increase 25% and a deep clean for systems that have been opened-up for a while

Usually when algae & cloudiness drag-on, it's because we've overlooked something - usually right in front of our face. As you approach the weekend, I would simply regroup and try to reflect on everything you've been doing and see if you've missed anything at all. It doesn't take much.
 
I did an OCLT.
FC at night - 24
FC in the am - 22.
FC now - 17.

I have a couple puck in the in line chlorinator to hopefully bring the CYA up a little. I’ll test again in a week or so. Would a bag of shock or two work better than adding cyanuric acid to a sock or floater?

I continue to get a gritty and fine sand on the bottom where the sides transition to the bottom.I vacuum it up and it returns in a day or so. Is this from the sand filter?

I may just cut some pvc, put in some unions and deep clean the filter this weekend to eliminate that possibility. The sand is only two years old, and has been subject to a couple SLAMS.

Any one have advice or a link on the best way to plumb the pump to the filter for easy removal of multi valve for deep cleans and sand changes?

Thank again Texas Splash and TFP.
 
Would a bag of shock or two work better than adding cyanuric acid to a sock or floater?
When you know your CYA is low, any of those items will work, but tabs will probably take the longest. I prefer the sock method with granules simply because they are quick, but use what you have. The calculator "Effects of Adding Chemicals" will give you an idea how much CYA should raise.
I continue to get a gritty and fine sand on the bottom where the sides transition to the bottom. I vacuum it up and it returns in a day or so. Is this from the sand filter?
This is concerning. If it is sand, then you might have a crack in a lateral or standpipe. You could try to capture some of it from a return jet by securing a sock or nylon over a return just to ensure it's sand and not something else.
I may just cut some pvc, put in some unions and deep clean the filter this weekend to eliminate that possibility. The sand is only two years old, and has been subject to a couple SLAMS.
While it's a bit of effort, I do think that's a great idea. It might even prompt you to inspect further based on the concern about the laterals. For re-plumbing, it's all personal choice and how you would like to route the PVC. Of course you'll take into account new unions which will serve you well in the future when you have to get inside the filter again. Once you start cutting pipe and dry-fitting as a test, you'll find a good path for the intake, outgoing, and waste pipes.
 
This is a shot in the dark, but should I start over. Let the FC drop, set PH to 7.2 - 7.5, and start SLAM over from “scratch”? There is very little change to clarity and greenness of the water.
I was going to deep clean this weekend, but wife talked me out of it since were renting. I could reach out to home owners but I’d hate to get a pool guy involved. Perhaps I could convince them to let me do the deep clean and put new pvc in, but since the sand is two years old, I’m questioning whether it’s really necessary.

I did a SLAM last season and it was wrapped up in about 2 weeks. This recent SLAM is getting out of hand, I’m going on 3 weeks since I found the algae hiding in the ladder post and opening the pool the first week of April.

Should I remove the deep end drain cover and look for algae there? I’ve searched this pool extensively, and that is the only piece I have not investigated?

Thoughts?
 
Should I remove the deep end drain cover and look for algae there?
Not a bad idea at this point. I'm still concerned about the overall SLAM though. It has been a long time. The color of the water in post #29 is misleading because in one shot it looks relatively clear, in the last it looks quite cloudy. Can you post a new pic or describe how it looks? Also, I don't recall if we ever asked ... are you on a well?

If you'd like, you can let the FC drop just long enough to validate the pH since it's been so long. Adjust the pH as necessary, then double-check your CYA and FC level. By any chance, is it possible your CYA could be higher than you think? You test the CYA outside right? Under a bright sunny sky at your back? Sorry if that's a repeat question, but the thread is getting long and I don't want to lose my place here. :)

Aside from everything in the pool that could possibly hold algae, there's only one final unknown spot - the filter. But go ahead and do the other things above first so you can re-group and catch your breath.
 
We're not on a well.

CYA is tested outside with sun at my back. I test and retest to confirm.

Shallow end @ 3' is clear, but doesn't reflect liner color well. Deep end is green but I can see the drain at 8'.

i wouldn't think CYA could be higher, all 4 tests I've done have been right around 20-30. Is it possible the regent is bad for CYA test? I bought a new one this season. I fill to bottom off label, CYA r-0013 to top of label, shake and mix, wait 30s, mix again and then test.

I'll update a new pic tomorrow. Im tempted to let the FC drop and start over.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.