Help me slam my green pool

DirtyPoolz

Active member
May 18, 2020
43
Northern VA
mknauss - one last question (i hope). I think my salt cell is bad. I cleaned it. I have a constant check cell and low salt. I threw in enough salt that it tested at 3.2k. The cell read different. I did the re calibrate procedure. But its slowly falling. Cell is out of sync with my testing again. Would the chlorine level of 10-15 (killing black algae) effect the salt making? Or is it most likely dead. There is flow etc.
 

DirtyPoolz

Active member
May 18, 2020
43
Northern VA
I feel like I am losing the battle against the black algae. Pictured is the shallow end. There is more in the deep end. We had a tiny bit last year. When we opened the pool this year it was everywhere.

Brushing multiple times a day. I have rubbed a trichlor tablet on it 2-3 times in the last two weeks. It does not seem like its changed. These pictures are two weeks apart. I have been running FC around 12. I got CYA up to 70 now. Now running FC closer to 20 as of yesterday. Brushing multiple times a day with metal algae brush. Do I just keep going?

5/28

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DirtyPoolz

Active member
May 18, 2020
43
Northern VA
OK - I have been operating under the assumption its black algae. Last year we had it. Opened the pool this year and this stuff is everywhere. The pool guy told me it was black algae. ( I have relieved the pool guy of his services). I just did the fingernail test and cant scrape anything off.

Last year I added some HTH Super Algae Guard for the black algae we got. Maybe 3 bottles over 2 months at the recommendation of the pool guy. I think they just did shock, and tricolor tablet to treat the black algae and told me to buy some algaecide.



I scrapped the vitamin c tablets we have on a spot. And nothing happened.
IMG_5321.jpg
 

DirtyPoolz

Active member
May 18, 2020
43
Northern VA
I assume concrete showing means its time to re-plaster. When we had black algae last year it was only it a couple of spots. None of these spots shown had black algae or were this color.

Maybe some more pictures will help...

Shallow end to deep end.
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IMG_5325.jpgIMG_5326.jpg
 

DirtyPoolz

Active member
May 18, 2020
43
Northern VA
So I had someone from a local builder swing by to look at replacing the plaster, coping, deck and patio. He said the plaster is old and needs replacing, its milling in the deep end etc. He took his big pipe he was testing the coping with and scraped off the material I have been trying to kill. He said its some kind of algae. He didnt think it was black algae or a stain.

Whats the next step after the stainless algae brush? Do i used a brillo pad? Sand Paper? Or just use way more force with the existing brush????
 

DirtyPoolz

Active member
May 18, 2020
43
Northern VA
I jumped in to get a closer look. He basically dug ruts in the pool. Underneath was white.
I can replicate what he did with a screw driver. I cannot get a sample. I can scrap the plaster out. Maybe it’s a stain.
 

mmcwhorter

Silver Supporter
Bronze Supporter
Jul 13, 2015
184
Huntingtown, MD
I have experimented with an alternative way to add CYA. It seems to work. I have used sock and skimmer pour methods in the past. My idea: Take a 5-gallon bucket and fill it up 80% using the pool water. Add on the order of 2 pounds of CYA and let it sit for about 2 or more hours. When you return the water will be clear and you'll see the CYA on the bottom of the bucket. After 2 or more hours...stir it up good, I use a sturdy plastic brush with a 2-foot handle...and it will indeed turn the water milky white, which is nicely dissolved CYA. Slowly pour about 1/2 milky white water into the deep end of the pool with the pump running. Refill up to 4 gals by dipping the mouth of the bucket into the pool, stir again, and repour.....continue this process 2-3 times and you'll notice all the CYA is gone. You'll see the milky white water in the pool spread out and dissipate. There may be a few very tiny bits of CYA making it to the floor of the deep end. I brush those toward the drain, they create a little white cloud as you brush... and I direct the particles into the filter. It's actually the same way I add 73-Cal Hypo, which these days is rare because my CH is on the high end and I love my new Pentair SWG IC-40.
 

mmcwhorter

Silver Supporter
Bronze Supporter
Jul 13, 2015
184
Huntingtown, MD
Oh, by the way....fire your pool guy. Tossing granular chlorine in the pool is a bad idea...as you can damage the bottom if it sits there too long. One time, a long time ago....some guy tossed 15 bags of Stabilized Super Shock in my pool, the idiot took my CYA up to 150. And he wanted to charge me $20/bag....really???!!!....I always pre-dissolve calcium, CYA, and 73 Cal Hypo in 5 gal buckets. I have had nothing but bad experiences with these "pool" people and now that we are on the TFT method using the TFT-100, all is well. I notice you are in N VA, I am in S MD. So we have similar environments...thus I strongly suggest that you SLAM the pool every year within 2-3 days after you open it after getting it balanced.....get an SWG and you are on auto-pilot. I bought a Nautilus CC Robot and now my pool is always clean (lots of trees) and almost maintenance-free, other than adding acid for pH. Love it.
 

DirtyPoolz

Active member
May 18, 2020
43
Northern VA
Vitamin c seems to be the answer. Since it’s everywhere an acid treatment seems to be in my future. Can I wait til end of August? Or is this something I should take care of now?
 

mmcwhorter

Silver Supporter
Bronze Supporter
Jul 13, 2015
184
Huntingtown, MD
Just to satisfy any curiosity you may have, AND because you are likely needing to replaster or acid wash anyway...next time you add acid to adjust the pH...try pouring 8-12 oz of some muriatic directly on top of a small area of the iron stains at the shallowest depth where stains are. The acid will sink to the bottom......let it sit for a half minute or so and then brush it away. Just to see if any stains go away. Take a good look before and after. Do this with the pump off and the pool water still. I know this is not something you'd do in a normal situation. But since you are likely ready to replaster of do an acid wash anyway, it's maybe a helpful test and what the heck...what are you going to lose anyway? For me, I love to "test" things. It's what I do for a living.

Alternatively, put some Vit C tabs in a baby sock ($1 at Wal Mart for six pairs), with a couple of pebbles, tie it off at the open end with a rubber band....and drop the sock directly on top of an iron stain. Let it sit for a day. I had a new roof installed and three nails went into my pool. I had 3 perfect outlines of roofing nails. Vit C took it out. And...I had five pairs of socks left over to give to my niece :)