White "Latte Foam" Covering Entire Pool on Opening

[mmcwhorter]

This is not a problem, I am just curious: what is the chemical cause of the "latte" foam on my pool surface. Photos attached.

I just removed the cover and all plugs, raked out all the leaves (not a lot this year!!!), ran my pool robot vac to get the stuff the leaf rake can't......and filled the robot's filters each time. Cleaned them, and did it 3x. Now the pool is very clean...water is a little blueish-green, and certainly cannot see the deep-end drains. Not a bad start I think......We had 2 inches of rain, I backwashed to get the level down and ran the filter 5 hours after which I noticed the "latte" foam. Hit it up with 2 gallons of 10% liquid CL before bedtime, and measured this morning. FC= 4.5, CC=0.5, pH= 7.2, CYA around 50 (?), CH=325 and TA around 100. Not terrible numbers for right at start-up. Water Temp: 51.4F. As to the CC...I would have expected higher CC this morning (lower FC) ....so that's odd. And I am really just curious about the "latte foam"...what causes it.

I don't have enough CL to SLAM right now, ordered a 25-pound Cal-Hypo 73% delivery and it'll be here tomorrow. I have 4 gallons of 10% liquid CL2 also. I have no doubt SLAM will make everything perfect, as six years in a row all I do is SLAM at opening, run my SWG and Pool Vac Robot...and yep, trouble-free pool

 

[Newdude]

I don't know the chemical cause, but it's commom during the early stages of a SLAM. Either any residual FC down below got right to work when you started mixing, and/or the 1st add did.

 

[mmcwhorter]

SLAM has not yet started. That will be tomorrow. I had added a bit of CL the day the cover came off, Saturday. But not a lot. One gallon, gets me to about 5 ppm. Two gallons yesterday evening, Sunday......Certainly not SLAMMING yet, that's tomorrow (Tues) when my Cal-Hypo 73% arrives.

 

[Newdude]

Yeah. It's not official yet. But any chlorine leftover or added doesn't know that. It just does its thing. I would have gone with 'pond scum' as a description, but I like 'latte foam' better.

The one year I got bit, it distinctively smelled like low tide.

 

[mmcwhorter]

I would say that there was a distinct odor like "sewer-gas" when the cover came off. Certainly, my hands smelled that way after digging into the skimmer returns to remove the Gizmo..... We got into the Jacuzzi spa before the Cl did its thing on Saturday...and that was a short trip into the Spa. Smells good now.

 

[mmcwhorter]

HERE IS MY SLAM PROCESS LOG:

After keeping the pool around 5 ppm for three days after cover came off... I began SLAM tonight around 7 PM.... Latte foam still there this morning when the pump is runningat 0700, turn it off, and an hour later it's gone...

With FC = 4-5ppm
CC= 0.5 or less (which is surprising two days in a row, I would have expected something at opening with 5 ppm FC.)
TA=90
CYA= 45 (somewhere in between 40-50 2 times)
pH=7.2 (yep, added just a little too much acid)
CH=275
Temp=+54 F
Pool was cleaned nicely with the Nautilus, water is blue-green (kind of pretty actually), can't see bottom drains in daylight....6 feet down

SLAM: added 4 pounds 70% CAL HYPO (left over from last year) and 1 gallon 10% liquid CL.
Pool Math says that should get me up to about 18 ppm.


I mixed the spa and pool water by draining the spa all the way down into the main pool, and then refilling from pool water. So they are both homogeneous.

It's 8:45, I'll check it at 10 PM and at 7 AM tomorrow.

 

[Newdude]

somewhere in between 40-50 2 times)

Round up. 41 to 49 = 50.

added 4 pounds 70% CAL HYPO (left over from last year)

Totally fine to do, but know that large adds of cal-hypo have been known to cloud up pools. I guess it's a wash right now as to why you can't see the bottom, but just something to keep in the back of your head.

 

[mmcwhorter]

I had not used any Cal Hypo before starting the SLAM, and the water was not clear. Blue Green....Think "Miami Dolphins Aqua, real pretty. Definitely not clear, can't see drains at bottom. I'll round up and use 50 for CYA.

I ended the SLAM process last night at FC=24.5 before retiring for the evening. To get there, I started around FC=4....I had added 4 pounds Cal-Hypo 70 (left over form last season) and for good measure, threw in a gallon of 10% bleach. The pool is remarkably more clear at 0800 today. It's subjective but I would say it passes the SLAM criteria at this time for water clarity. I can see the drains at 6 feet, whereas yesterday could not. But did not pass OCLT. Went from 24.5 to 20.5. As to CC, it measured 0.5. So, if I round up to CYA=50, my SLAM level is FC=20. I added a gallon of liquid CL at 0800. Won't test again till noon. It's going to be cloudy here all day, with a little occasional rain expected.

I have not connected my SWG, using a pass thru pipe. The plan is to do so after passing SLAM and the level of FC drops to below 10. I'm hoping the water will stay above +52F so it will produce Chlorine after SLAM. We are having an exceptionally cold early spring here. Won't even hit +70F till April 15 (per long range weather estimates).

I work from home so it's easy to run the SLAM. I see the clouding using Cal-Hypo for a few minutes after it's added, but as it dissolves it goes away.

 

[Newdude]

But did not pass OCLT

A fail is a fail. Do not pass go. Do not collect $200. Proceed directly to more SLAM

 

[mmcwhorter]

Yes...indeed. A fail is a fail. So from a measured FC = 20.5 at 0800 (failed OCLT) and adding one gallon of 10% liquid CL at the same time.....I checked the FC at 3 PM...and was happy to see it at 24.5. CC= 0.5. I would have checked at noon...but it started raining. Pump running, pool clear, brushed the bottom and sides. I always pull my Nautilus CC pLUS out during SLAM, so it can't help clean.... Filter pressure was unchanged, even with a little DI slurry added when I began SLAM yesterday. It seems adding DI makes the pressure go up more quickly. We have had a very cloudy day today....a high of +46F...sure wish it would warm up... My WS-2902 weather station (which I think measures rain very accurately) says we have had 0.48 inches since it started at noon. All looking good. Hope to pass OCLT this time.

 

[mmcwhorter]

The second day of SLAM results:

This morning the water is absolutely crystal clear, I can see the Phillpis head screw slots in the screws on the floor drain covers. CC is 0.5.
But Overnight CL Loss was 2.0.

Now I ask: we got 1.2 inches of rain yesterday between noon and 0600 today....and there are about 100 dead earthworms in the bottom of my pool.
How much (if any) will this skew the result of the OCLT?

 

[Newdude]

How much (if any) will this skew the result of the OCLT?

Effectively none. If you got 1 inch of fresh water, that'll drop your FC 1.6% from 20 to 19.68 in an average depth 60 inch pool, which is undetectable or chalked up to the 1 drop test variance.

 

[mmcwhorter]

Yes, I get that math But what about the dead earthworms. Are there any potential organisms in the rain that might affect? It seems like I have heard many times that rainstorms will have an effect on algae production in pools. I am making the inference that there may be something in the raindrops, such as an organism that needs to be disinfected.

 

[Newdude]

It seems like I have heard many times that rainstorms will have an effect on algae production in pools

Every. Last. Friend. I. Knew. With. A. Pool. went green/cloudy with every storm. I fought against joining them by getting a pool.

They were either teetering on unsanitary, or full blown smack in the middle of PathogenCity for a little bit of rain to matter.

If you found a long decaying pile of long dead earthworms and threw them in, maybe, just maybe, you'd see a small loss. Any that went in fresh and died are a drop in the proverbial 23k gallon bucket and instantly sterile, with 22,999.9999999999 gallons of SLAM water to spare.

 

[JamesW]

But Overnight CL Loss was 2.0.

You either pass or you don't.

If you do not pass, the SLAM is not complete.

Maybe the rain and worms had some small effect, but that is mostly irrelevant.

Even if they had a big effect, it does not change the fact that you did not pass the OCLT.

Once you pass the full SLAM criteria, maintain sufficient FC at all times.

 

[Newdude]

Lemme play Devils Advocate on myself and let's say the rain/worms made a dent in things. It's a fail, and one more day is needed until we pass. Tomorrow's passes and we're good to go. Or tomorrow's fails and it's one more day.

 

[mmcwhorter]

well, I failed again...had a 3.0 Overnight CL Loss. CC=0.5 and the water is very clear and there is no visible algae. Visible....that is...Still have 50 dead earthworms....the new "Baker Safe Drains" won't suck them in when I brush toward the drain area at the deep end. I try to keep my Nautilus CC Plus out of the pool at high CL...and I have not replaced the old pole vac/hose method to vac since they both broke 2-3 years ago.

The water is on the order of +54F, and I am now thinking there is algae behind the bezel of my deep-end light fixture. I doubt I have the fortitude to get in the pool at +54F and remove and clean the bezel. I did remove and clean it about 5 years ago in the middle of a good warm summer, water was +85F and there was a lot of algae gunk. I'll take another look at both Weir doors...they were cleaned when I pulled out the Gizmos. Also, I also have those rope holders at the shallow end....little plastic inserts embedded in the wall to hold the ends of a floating rope barrier at the shallow end (kid proofing I would guess) ...I've seen algae in there too.

If I am not going to find/remove the algae that's hiding out in the light bezel till it warms up, I think it best to suspend the SLAM, hook up the SWG and hope we stop having overnight lows in the +35F each day. Last year I opened late to a greener pool because we went on a 10 day vacation in mid-April, this year perhaps I overcompensated. And it's colder this year too.

 

[duraleigh]

The SLAM process is used to clear and sanitize your pool.

If you choose to stop the SLAM before it is complete, it's almost as if you never SLAMed to begin with. My suggestion would be not to shortcut the SLAM but continue it until it is complete.

The SLAM article is quite thorough and there is NO wiggle room. Follow the article verbatim and your pool will clear. Daily, if you can,Vacuum and brush the earthworms and any other debris out of your pool.

 

[mmcwhorter]

yes sir, I get all that. Have read it thoroughly. My FC is around 22 right now, my SLAM level is 20....as I remember. CYA = somewhere between 40-50. So round up. I have been hovering during slam between FC= 24 and 30. I'll double-check cleaning the Weir doors and rope stanchions....toss in another gallon of 10% and give it another day. I was hoping after opening my pool that the CYA was a bit lower. Maybe like 40....Surprised it didn't drop more over the winter.

 

[mmcwhorter]

PERSISTENCE: Continued the SLAM another day and PASSED. OCL was 0, and CC was 0.5, The Pool is so clear I can see the Phillips heads at the bottom clearly.

Prior to running the OCLT, I cleaned out the rope stanchions (4) and not much gunk came out. I did brush again the Weir doors and strainer areas. Did not address potential algae in the recesses of the pool light.

I have an idea why I might NOT have passed the day before....this is a guess and can't prove it. I think I had a minor flaw in the process: I was ONLY adding CL to the pool, and then assumed that running the returns back into the pool and the spa for 1-2 hours would get me to the same equilibrium FC level in both pool/spa. If not, then the spa would continue to dump lower concentration of FC overnight back in to the pool, where the sample FC was taken...thus lowering the FC in the pool. Just a guess, the spa is 1500 gallons, the total is 23000. Lets say I raised the pool FC by 7, did the spa catch up in 2 hours? Who knows?

So, two hours after raising the FC to estimated fc=27 (Target SLAM = 20) I changed the valves to completely drain the Spa into the pool late last evening, then refilled the spa...to get both spa and pool mixed together at same FC. I took the OCLT sample then.

Alternatively: next time I could close off the spa completely and just keep it at the SLAM level or higher while the pool is Slamming.

Anyway, it passed and I'll be connecting the IC-40 later today. Now, if we can just get the morning lows out of the mid-high 30's, the pool water will start to warm up....Like all years past, my IC-40 and my Nautilus Pool Vac provide a trouble-free pool after SLAM> (ok, a little MA here and there too)....