On the right track?

[Ericwood73]

Do to a combination of factors my pool sat without any chlorine for around 3 weeks. I started my process Thursday night with 0 FC and 0 cya. I got my tF100 test kit (thanks tftestkits.net for shipping so quickly), and started working to get my CYA to 300. I put 1.5 lbs of CYA in a sock and let it sit overnight. The next morning, my CYA was only around 20, so I put another 1.5 lbs in. Within a few hours, it was holding steady at 30. I began my treatment with 6 gallons of chlorine (I mistakenly used the Shock FC for target for the SWG target of 70, instead of 30). In a half an hour, I was reading 1 ppm FC, so I added 3 gal. Next cycle it was around 2 so I added 2 gal. By early evening, I was out of FC and I started using 68% Cal Hypo. I ended up adding 3 lbs of cal hypo last night before going to bed to try to get it to have some chlorine this morning. This morning I measured 1 ppm. I knew I had to run to the store to buy more so I spiked it with my last 5 lbs of cal hypo. That got me to 15 ppm fc. A half hour later it was 12, another half hour later it was 10, so I added a gallon. Now I pretty much read 10 ppm every hour and I add a gallon. This is what the pool looks like now.
View attachment 79991
At this point I have added 15 gallons of 10% chlorine + 8 lbs of 68% cal hypo. I can hold 10 ppm FC by adding 1 gallon of 10% every hour. Late yesterday and earlier today I saw large amounts of film on the surface, which I assume is dead algae. Now I see only a very fine film. I know this is a process and I understand the process correctly, keeping the FC high will clean up the algae. Does this look like what you would expect given the process and where I am in that process?

 

[Ericwood73]

Should have added that CC is reading about 2 ppm.

 

[AimeeH]

HI Ericwood. Welcome to TFP

Sound like you are on the right track. If I read correctly, you added enough CYA to get to 30? Have you been able to measure CYA?

I'd go with liquid chlorine only and stop with the cal hypo. You need to be shooting to maintain FC at 12 IF you are at 30 CYA testing as often as necessary and dosing with liquid chlorine. Brush brush brush and keep your filter running 24/7 during SLAM process.

 

[RobertScalchi]

CYA of 30 is a perfect baseline to SLAM at FC 12ppm. However because algae, organics and sun uv consume chlorine at a rapid pace, i am wondering just how much sun from the course of a day is eating up your chlorine along with the algae?

What time does the sun hit your pool from am to pm?

You might want to bump your CYA to 40 if you have a lot of sun and SLAMat FC 16 ppm. Your call...on how much chlorine you want to dump in verses losing it a little faster or slightly slower in a 24 hr time frame. Or you can stick with CYA 30 and SLAM at that ratio and see if chlorine consumption goes down as water progresses to clear. Otherwise you are doing awesome!!! SLAM away. Make sure you brush good to break up the protective biofilm, and drag the floor with the leaf net and vacuum blind if you have to. The faster you get the debris out of the pool and the longer you run the filtration and longer you sustain the SLAM, the quicker this will clear up.

The water color should go from green to, clear aqua green, to cloudy blue, to crystal clear blue.

Also to mention I don't know what kind of filtration system you have whether it's de, sand, or cartridge you might want to put that in your signature. Either way let the pressure dictate to you when to clean or backwash. You want the pressure to rise 20 to 25% above normal clean operating pressure. You want the filters to be a little bit dirty so it filters out finer suspended debris as it loads up. Another little help is skimmer socks or hairnets over the skimmer basket.

 

[Ericwood73]

Thanks Robert and Aimee. I have measured CYA twice since I started and it has stayed steady at 30 ppm. Pool got very little sun today and none yesterday due to clouds and rain. The filter is a Pentair C&C 150 or maybe 200 (can't tell without counting the pleats on the filter). I cleaned it right before I started the process and was planning to leave it alone unless the PSI spiked. Should I over chlorinate tonight so I still have some in the morning? It seems I'm still losing 3 to 4 ppm per hour so by morning I suspect I'll be back to no FC.

 

[RobertScalchi]

Other than losing the FC for your CYA ratio, it never hurts to over chlorinate by 4-5ppm. In other words if your cya is 30 and your shock level or SLAM is 12 PPM. Then shooting for 16 or 20ppm FC nothing wrong with that, but because your CYA is 30 you will lose that 6 FC fairly quick if algae or sun uv is comsuming it. It's a balancing act and an interrelationship between the two components. But when you're trying to clear algae and kill it and never hurts to overshoot other than the FC loss. So yeah do it do it tonight if you're chlorine loss is that rapid.

 

[kellyfair]

Don’t forget to remove any rubbish in the pool, that will cause SLAM to go longer.

 

[mknauss]

There is no reason to overshoot SLAM levels. The excess chlorine burns off rapidly and is a waste of money.

The chlorine is still killing algae as long as FC is above the minimum based on the CYA.

Take care.

 

[RobertScalchi]

MKNAUSS. Those 4 extra ppm's on a SLAM. I agree it can be a waste of chlorine in theory and practice. But I was wondering can the loss be comparatively measured and sustained in water tests where the extra ppm of FC was poured in at nightfall with no UV exposure, then measured again before daybreak. I understand most likely the algae or any organics is most likely going to consume that extra chlorine, when algae is present even during nightfall when there is no UV exposure

The reason why I bring this up is because I've heard of pool owners on here sometimes properly maintaining their FC to CYA ratios during a SLAM, and they weren't able to get past the aqua green hurdle, but when they bumped the chlorine 2 to 4 PPM over the CYA to FC ratio, it got them to cloudly blue the next morning when implemented overnight.

It could be argued that in one or two of those cases the CYA was improperly measured

I was curious even if you were to conduct a test where the conditions are perfect, where the CC was 0.5 or less at night fall, and the water was crystal clear, not having algae consume the free chlorine, would you still lose that extra 2 to 4 PPM overnight? Or would it maintain itself until UV exposure was present and burned it off?

I know this is probably more of a question for chem geek. When time, I will slightly overshoot my FC target this week at nightfall just to see what happens the next morning since I am crystal clear, for experimentation purposes

 

[domct203]

I don’t see any major harm in dosing 10-15% (2ppm) over your SLAM target, especially when you know that is will be consumed within an hour by all the algae.

As mentioned, once you cross that 40% CYA ratio, the chlorine will burn off quicker from UV, so don’t go overboard as it is just waste.

 

[Ericwood73]

Still in aqua stage

View attachment 80036

I checked my CYA in sunlight and it was closer to 20 so I added another pound. It's measuring 30 now, but I'm having to add a gallon an hour just to keep FC at 8. At this rate I'm going to burn through the rest of my chlorine before sundown and have to buy more. Should I maybe just hold at 8 until sundown and then boost it higher?

 

[Ericwood73]

1/2 gallon an hour is keeping me right at 8 ppm. I'm thinking that I'm losing some to sunlight because yesterday, when it was overcast, I could hold 10 with that amount. What is the minimum level that will keep algae from growing? I'm thinking to hold that level and then once the sun goes down, boost to recommended shock FC.

 

[Ericwood73]

I just saw on another thread where mknauss said that the number on the liquid chlorine bottle indicated when it had been filled. All mine are 17 191 or earlier. I guess my chlorine is substantially degraded? Glad I've put in almost 30 gallons of the stuff at almost $4 a gallon!. If I can't find any newer chlorine guess I'll have to use cal-hypo? My CH is really low so I'm not too worried about raising that.

 

[mknauss]

There is a number 18XXX on the bottle. The XXX represents the number of days in 2018 the bottle was filled. Look for stuff less than a couple months old.

So --- if your bottles show 17191 or earlier - you have salt water essentially.

Are you getting the expected rise of FC when you add the product to your pool?

 

[Ericwood73]

When I first started I dumped 6 gallons in and got to 8 ppm. Since then, not much of a rise. Much bigger rise with the cal hypo. I just figured that I was losing it almost instantly to algae destruction. But now it makes sense why I haven't been able to keep the FC up, why the cal hypo was os much more effective and why the chlorine yesterday was more effective than today (150 days difference in fill date).

 

[Ericwood73]

Day 4. Lost most of the FC overnight. Went to HD and got Chlorine that was only a month old. Added 2 gallons at 8:00 and brushed. Added another gallon at 9:00 when I measured 7. Pool is starting to get a nice blue color, but FC loss is still massive. I'd say I'm almost back to where I was before the algae took hold. Still can't see the bottom. A pool service guy I've talked to on the phone recommended Revive, so I bought some before I found TFP. Mind you I've never paid his company a dime and I didn't buy the chemicals off of them. He said they use this flocculant on cloudy pools and it works great. I'm sure I still have some organic material on the bottom because I can see it bubble up when I brush, but I can't see it to vacuum it up. I also have no MD on my pool, only a single skimmer. Given that:
1. Does Floc make sense in my situation?
2. Filter pressure is reading normal, but I'm sure the filter is gross with all the dead algae, will cleaning it help clear the pool faster?
3. Unrelated to pool clearing, I have an SWG to install as my feeder broke and I didn't want to buy tablets anymore. Does it make sense to get that going to help offset some FC loss, or should I wait until SLAMing is done. I'm worried I may be bankrupt by the time I'm done buying chlorine.

View attachment 80094

 

[Ericwood73]

Day 5. Overnight FC loss of 9. CC at 1ppm The green is mostly gone, but I'm still losing 90% of my FC overnight. Is it normal to experience this much chlorine loss at this stage (cloudy blue)?



I can't babysit this today, and I'm out of chlorine. Should I just boost this to the shock FC and it fill be okay until I can get home this afternoon?

This is what my filter looked like, so I gave it a good hose down. No idea if it will help or not

 

[kellyfair]

You absolutely should clean your filter periodically.

Linking SLAM article for a refresher read.

 

[zea3]

It is time to replace that cartridge! It should not be collapsing on itself like that. As for letting the pool sit until you have more time and bleach, it will be fine until you get home. You can't let it go for days at a time but a few hours is fine.

 

[Ericwood73]

Day 9 of SLAM.

OCLT 4.5 ppm CC 1.0 ppm.

I did order a replacement cartridge. It arrives Monday. And the Duda socks arrive Wednesday. I realize that with the holes at the top of the filter exposed, I was putting dirty water right back in the pool. That's also why the pressure gauge never read higher. I wrapped some duct tape around the holes (which had the added benefit of tightening up the seals so the filter sits higher and doesn't sag as much.) Now the filter is hitting 20 psi (from the starting pressure of 10 psi) twice a day and I am hosing it down each time it does. It's definitely taking longer to reach that pressure though and the filter is less dirty each time I clean it. I added a skimmer sock last night and the pressure was barely 20 psi. Most of what I hose off of the filter is pale green film (I'm assuming that is dead algae). I do notice a pungent chlorine smell when I remove the filter housing as though the chloramines were high, but I wonder if that is just proximity to my now defunct feeder. I think all this attention to filtering out stuff is starting to pay off. You can see full detail in the seats and the riser of the second step is barely visible. Also I can see my returns from the surface pretty clearly.

I'm still not sure what is eating up my Chlorine. I brush every day and get maybe 5 or 6 leaves coming up off the bottom. Yesterday I vacuumed the entire pool and got very little to show for it. I did find live algae in the skimmer surround so I scrubbed that out really well. I also have a port next to my skimmer that I believe is actually for a pressure side cleaner, but the idiot who built the pool plumbed it into the suction side of the pump. There appears to be algae growing in that line. I have the valve shut so the water in that line can't get into the pump, but the spring loaded cap wasn't fully closed, so I was thinking maybe algae could be entering the pool through there. I scrubbed out what I could reach, snapped it shut, and made sure it was screwed tightly into the wall. I also scrubbed the bottom side of all the ladder steps. I found the location of the light niche, by feeling around the wall with a pole and scrubbed it vigorously with the pool brush. Until I can get in the pool and examine it visually, I won't be able to be 100% sure there is no algae in there, but I didn't see anything coming up when I scrubbed it. So I believe the chlorine loss is caused by organic material that I still cannot see on the bottom of the pool and my priority right now is getting clear so I can get rid of it.

Would it make sense to pause my SLAM and run my SWG until I can get clear so then I can surgically strike whatever is causing the chlorine to get used up. I feel as though I am just throwing chlorine away at this point. If not, is it safe to get in the water and visually inspect the pool bottom for organic material that might be eating up the chlorine?