Have I set myself up for failure, and how much chlorine have I wasted?

[Oregonpool214]

Hello all. I'm feeling a little sheepish tonight as I've spent the last 4 or 5 days trying to clean up my swamp, and overlooked my CYA to chlorine SLAM value, so have (I think) been chronically UNDER chlorinating during my SLAM. But, I'm also running into some results I don't quite understand.

The backstory: I helped my son collect tadpoles from our pool, before I started cleaning it up (that gives you an idea of the shape it was in). Neglect over the winter as we dealt with a near-complete house reno after a huge water leak/flood. I balanced everything except my chlorine before adding my first chlorine earlier this week. Since then, I've been testing multiple times a day, not trusting various results, and generally just fooling around (I NOW believe, of course thought I was doin' right by the pool back then). Then, I look back at the CYA to CHLORINE for SLAM level, specifically, and see that I need to hit something like 20 (24 if I'm over shooting CYA reading) for my CYA of 50. Simultaneously, I see my 31 empty chlorine bottles and want to just shoot myself in the foot. What I have is a beautiful color pool, but cloudy cloudy. It doesn't look green. And I've been vac'ing, sweeping, backwashing if filter pressures suggest it, but just not seeing any progress. I bet I can see 5 feet down, and das about it.

Here are the interesting things:
(1) My CC has not been outrageous.... in fact sometimes I hit, very convincingly, 0.2CC.
(2) I'm also dealing with persistent DIPPING in my PH, despite adding bicarb, using ONLY liquid chlorine, and even doing some aeration.
(3) A few nights ago, I hit a convincing 18.6FC and then a recheck in the am of 16 something, and I thought "oh, this is IT!", but then later in the day it acted like I hadn't even added the 3-4 gals I had added earlier.

Will all these things clear up when I get my FC up above 20? Or is there something else going on? I just skimmed over something about ammonia - could that be contributing to my troubles?

I'm a bit at a loss, even though I've had good success with managing my pool through TFP methods in the past. I'm in over me head, me thinks. I've tried to keep up all additions. notes, and results in my Pool Log, if peeking there would assist in diagnosis....

 

[IceShadow]

If you’re holding any FC at all it’s not ammonia so don’t worry about that.

A tip: use 10ml water samples and divide drops by 2 to use less reagent. That’s accurate enough for our purposes.

Sounds like you were underchlorinating during the SLAM but if it went cloudy blue then it was still enough to kill most of the algae. Have you done an Overnight Chlorine Loss Test?

Cloudiness is something that just takes time to clear as the filter works through the dead algae, and if it was really bad, then there’s a lot of that to remove. Keep backwashing when pressure rises by 25%. If you don’t see improvement you can always check for hidden sources of algae in the pool (light niches, ladders, weir doors and skimmer throats, etc.) and even try a deep clean of your sand filter, but for the most part it’s patience you need. The pool didn’t get bad in a few days, it will take more than a few days to filter it all out.

 

[Oregonpool214]

If you’re holding any FC at all it’s not ammonia so don’t worry about that.

A tip: use 10ml water samples and divide drops by 2 to use less reagent. That’s accurate enough for our purposes.

Sounds like you were underchlorinating during the SLAM but if it went cloudy blue then it was still enough to kill most of the algae. Have you done an Overnight Chlorine Loss Test?

Cloudiness is something that just takes time to clear as the filter works through the dead algae, and if it was really bad, then there’s a lot of that to remove. Keep backwashing when pressure rises by 25%. If you don’t see improvement you can always check for hidden sources of algae in the pool (light niches, ladders, weir doors and skimmer throats, etc.) and even try a deep clean of your sand filter, but for the most part it’s patience you need. The pool didn’t get bad in a few days, it will take more than a few days to filter it all out.

Thanks! Glad to know it’s not an ammonia (or something else scary) issue.
The closest I’ve come to the OCLT is from last night - or maybe the night before (they’re all running together), where I had 18.6FC at 10PMish and 16ish the next am.


My filter pressures haven’t been ridiculous either - I usually ride at about 17 after replacing sand and new filter at the beginning of last summer, and I’ve been riding at 19 most of the time the last week.

Oyyy - being patient is hard! Especially when I keep throwing in chlorine and see no progress. So, if I do a OCLT tonight, and i only lose 1ppm FC overnight, I can stop slamming and jsut let the filter do its (pokey) thing, right? Or, if my CC is less than .4 (like it was this afternoon), can I stop slamming even though I didn’t actually ever reach my SLAM values? If the indication for a slam is high CC, and mine isn’t ..... is it still warranted?

As far as hidden sources go ..... I don’t see anything from what I can see. But I can’t see the bottom of my deep end / main drain. Otherwise my walls and what I can see are clean and beautiful. We jsut painted it fresh last year pre-season. Would I see rapidly eaten up FC if I still had a major algae source somewhere isolated?

 

[IceShadow]

If you’re losing 2.6ppm FC overnight then you’re still killing algae. Even with just cloudy water you should continue the SLAM. It’s important to be sure you don’t backslide as you filter out the dead algae.

Take a photo daily at the same time with your pole in the water at the same spot to try and gauge progress. Have you backwashed at all yet? Might be worth doing once to ensure you have the right starting PSI.

 

[kellyfair]

No, you don’t stop the SLAM until you meet three criteria - water is clear, you pass the OCLT and your CC is .5 or less.

You stumbled into getting the green to go away, but you need to keep going at the proper level until all three criteria are met.

 

[Oregonpool214]

No, you don’t stop the SLAM until you meet three criteria - water is clear, you pass the OCLT and your CC is .5 or less.

You stumbled into getting the green to go away, but you need to keep going at the proper level until all three criteria are met.

Thank you!

If you’re losing 2.6ppm FC overnight then you’re still killing algae. Even with just cloudy water you should continue the SLAM. It’s important to be sure you don’t backslide as you filter out the dead algae.

Take a photo daily at the same time with your pole in the water at the same spot to try and gauge progress. Have you backwashed at all yet? Might be worth doing once to ensure you have the right starting PSI.

Good idea with pole in water. I’ll try that. I backwashed right after I went from green to blue, had it up to 25psi and settled back down to 17/18. I even did it once when it was at 17 jsut to see what it looked like coming out and it was mildly cloudy output only for a second then back to pool-water clear.
You mentioned something for deep cleaning filter - is that something from a DUN DUN DUN pool store?!

 

[kellyfair]

Thank you!

Good idea with pole in water. I’ll try that. I backwashed right after I went from green to blue, had it up to 25psi and settled back down to 17/18. I even did it once when it was at 17 jsut to see what it looked like coming out and it was mildly cloudy output only for a second then back to pool-water clear.
You mentioned something for deep cleaning filter - is that something from a DUN DUN DUN pool store?!

Nope. It’s pretty low tech... just requires a hose. Let me find link for you.

 

[IceShadow]

Deep Cleaning a Sand Filter

This post will walk you through the anatomy of a sand filter, and then provide a video at the end for how to deep clean your sand filter. The filter used in the photos and videos is a Hayward S180T top mount sand filter. The images are of a similar filter. Obviously not all filters are...

www.troublefreepool.com

 

[kellyfair]

Dustin is quicker than me!

 

[IceShadow]

Our first year here I was concerned we were getting sand in the pool and that a lateral might have broken in the filter. My wife and I shop-vacced all the sand out, put it one load at a time on a wheelbarrow, and ran water through it. It was BAD with pine needles and grey junk. After it was rinsed clear we put the sand on a wheelbarrow and went on to the next bucket load.

Last year and this year I just did the deep cleaning at opening like the thread describes. Much better to deal with.

 

[ajw22]

Your pH testing is invalid when your FC is over 10.

Just test FC and CC during the SLAM Process. With occasional confirmation of your CYA level.

Leave your pH and TA alone until the SLAM Process is completed and your FC is below 10.

 

[Oregonpool214]

Update on the swamp: I can now see my vacuum head about 6ft down! Pool owner patience is such a thing! I finally have CC of 0, and holding chlorine a bit better ...... had a weird drop in my CYA, which I can only attribute to my FC level getting high (per prior suggestions /experience from others on here). I’m finally able to see the bottom of the shallow end clear enough to see white silt (??) on the bottom, which I jsut got done vacuuming. Still going to keep FC bumped up, but now using a lower goal then previously due to my decrease in CYA.

I SO appreciate all the help, gentle reminders, and great knowledge here.