Stains and Plaster Bumps

[NewB77777]

Hi,


I'm a new pool owner who asked couple questions here months ago, and I was waiting new pump rebate after draining and filling new water.
However it doesn't looks like Edison will do rebate again and our new water got dirty again, so I just bought a new pump(without rebate) and just re-drained water again

Question 1.
I want to clean again before filling new water.
However one pool guy told me that after pouring liquid chlorine on wall, leave chlorine and wash with water after 1 or 2 days, instead wash with water in 10-15 mins.
He told me that it will make wall more whiter.
Is it true?

Question 2.
Size of our pools is about 20,000 gallon with spa.
And The pump that I just purchased is Pentair Intelliflo Variable Speed Pool Pump (3HP) 011028
And the filter we have now is pentair Clean & Clear plus CCP 320 filter
However the pool guy told me that it is better to buy bigger filter or add cyclone to the current filter[MultiCyclone 16 Centrifugal Pre-Filter] because our pool is big for the current filter.
Is it true?

Question 3.
There are couple of black algae residue in our pool
And the pool guy told me that he can sand it with fine sand paper.
Is it okay?

Thank you in advance!

 

[kimkats]

You state that your "water got dirty again". Can you explain what you mean by that?

What are you using to test your water? What are you using to add chlorine to your pool?

Asking that I will say you NEED to put water back in the pool before the shell pops out of the ground! There is one person that just posted about their shell coming up 6" when they had it empty and it rained hard in their area We can help you clean your plaster even with water in it.

 

[Texas Splash]

The 320 should be fine, although you might have to clean the carts a little sooner than if you had a larger filter. I have a single cart in my 18K pool, and it works. With a 320, you won't have to rinse your carts every month like I do, but it should be okay. I would try it first before investing in any pre-filter. Maybe that's just the pool guy's way of trying to make a few bucks. The key to all this though is TFP-clean & clear water. If your water gets dirty or has algae, all bets are off. Filters get clogged quick with algae, so the filter's performance depends on your accurate home testing with a TF-100 or Taylor K-2006C.

The black algae can be brushed or I suppose sanded. Depends on how deep it has rooted-in to the plaster. Brushing, exposing the roots, then chemically treating should help considerably. Also see: Black Algae - Trouble Free Pool

 

[NewB77777]

You state that your "water got dirty again". Can you explain what you mean by that?

What are you using to test your water? What are you using to add chlorine to your pool?

Asking that I will say you NEED to put water back in the pool before the shell pops out of the ground! There is one person that just posted about their shell coming up 6" when they had it empty and it rained hard in their area We can help you clean your plaster even with water in it.

After draining, I filled water. However I didn't install new pump(old one broke) because I thought Edison would start new rebate for variable pump.
I have poured chlorine weekly, and one day I found it is too dirty.
So I just purchased variable pump, and I asked a pool guy to install it.

He told me that our filter is not big enough(he was the only pool guy who told me like that. Others didn't say nothing about it)
So he told me it is better to change bigger filter or De filter, or install [Waterco WC200370 Cartridge Filter MultiCyclone 16 2 in] by keeping current filter.

 

[kimkats]

Dirty water is almost always a lack of enough of enough chlorine in the pool as well not keeping the other things like pH and TA level. A smaller filter can do the work. It just means you might have to clean the filter more often.

 

[NewB77777]

Like I mentioned above, we drained all water, and I already poured chlorine again along side pool to clean green stuff.
And it looks like black algae doesn't grow at all from the last cleaning.
The black algae residue looks same like when I cleaned months ago.
I attached couple of picture of black algae residue.
However I'm still not sure if the black algae already die, or do we need to brush more before refilling water.
IMG_5072) we took a picture months ago before we removed black algae
IMG_5088, 5089) we took a picture months ago after I brushed and poured chlorine wash
As you can see, some of residue still have black things in there.
Please let me know.

And, is there a way to remove all residue, or is it impossible to remove the spot?
I tried to sand with 80 sand paper. However it doesn’t looks working.
I will try with 60 or 80 with orbital sand machine
Thank you.

 

[Texas Splash]

"NewB", after seeing those latest pics, I'm having doubts about it being black algae. Almost appears to be something trying to surface from below. Let's get another set of eyes on those pics. @JamesW, what do you think?

One last thing though .... have you ever used copper-based algaecides or any "Blue" products? Do you have any dry acid laying around to where you could try some (in a sock or nylon) on either of those spotted areas? I'd be curious to see if it does anything.

 

[NewB77777]

"NewB", after seeing those latest pics, I'm having doubts about it being black algae. Almost appears to be something trying to surface from below. Let's get another set of eyes on those pics. @JamesW, what do you think?

One last thing though .... have you ever used copper-based algaecides or any "Blue" products? Do you have any dry acid laying around to where you could try some (in a sock or nylon) on either of those spotted areas? I'd be curious to see if it does anything.

No I didn't use any copper based algaecides or any blue produces.
I don't have any dry acid. However I can try.
Please let me know which produces should I use first, and which brand products.


BTW, If you need, I can take more close up pictures[I just added couple more pictures]
Thank you!

 

[Texas Splash]

Let's give @JamesW time to catch up and review those pics in post #6 and we'll go from there. Thanks for the info.

 

[NewB77777]

I know the Previous owner of our house like to go fishing.
So he might had brought some weird algae from ocean or river to the pool.

 

[JamesW]

Black algae is a type of blue green bacteria. It's called cyanobacteria from the color cyan, which is greenish-blue.

Black algae is like mold where you can scrape it off.

The spots don't look like black algae, but I'm not sure what they are.

The spots are too black to be black algae. Black algae will usually have some green color.

 

[NewB77777]

Okay, then do you think It is better to try copper based algaecides or any blue products before filling water?

 

[Texas Splash]

Okay, then do you think It is better to try copper based algaecides or any blue products before filling water?

You never want to use anything like that. Avoid copper (or Blue) products because once copper is in the water, it's not coming out unless you change the water. Since James confirmed what I though, that means the discoloration is from something else. To see if the spots are from copper staining, you could try a little dry acid as I mentioned before (in a sock or nylon). Leave i on the stain for 3-5 min to see if that changes anything.

Say, did you ever try Vitamin C? Some of your last photos make the staining look light brown like iron. As if a washer or something fell in the pool and laid there for a bit making the stain. If you haven't done it yet, try some Vitamin C tablets directly on the stain.

 

[markayash]

I tried the cyclone a few years back and ended up throwing it away. It didn’t catch a lot of stuff and was hard to mount without taking up a lot of room. My issue was tree droppings and they just seem to float and past the cyclone. It did catch some sand looking dirt but very little.
Plus they aren’t cheap.
Take that money and bigger filter and use hairnets on your skimmers

 

[NewB77777]

You never want to use anything like that. Avoid copper (or Blue) products because once copper is in the water, it's not coming out unless you change the water. Since James confirmed what I though, that means the discoloration is from something else. To see if the spots are from copper staining, you could try a little dry acid as I mentioned before (in a sock or nylon). Leave i on the stain for 3-5 min to see if that changes anything.

Say, did you ever try Vitamin C? Some of your last photos make the staining look light brown like iron. As if a washer or something fell in the pool and laid there for a bit making the stain. If you haven't done it yet, try some Vitamin C tablets directly on the stain.

Like I mentioned above, I already drained all water. So I can use copper or blue products if it helps.
And the spot has not only color, but also has some kind of mark. So I can feel something when I touch it.
The max height of the mark is about 1/32 inch.

I will try dry acid and Vitamin C.
Do I have to moist dry acid and Vitamin C, or just leave it on the mark without moist?

 

[Texas Splash]

Do I have to moist dry acid and Vitamin C, or just leave it on the mark without moist?

Yes, I would wet it a bit. Try the Vitamin C first. If that shows no change, then try the dry acid. Of course the dry acid is much stronger, so be careful with your hands and make sure to rinse the area after you've tried the test - maybe about 3-5 minutes.

Like me, in your area you probably never really "close" your pool or have a need for algaecides. But if for some reason you ever do need to use an algacide, make sure it's a Polyquat 60 product as those contain no copper by- products.

Let us know how the Vitamin C and/or Dry acid test goes.

 

[NewB77777]

Today I saw small spot [I'm not sure if it was there, or recently occurred]
And I scraped it with a metal scrapper, and I recored it.
I though it was black algae. However now, I think it is more likely calcium buildup.
After multiple scraping, I could remove the build up, however I couldn't remove the residue completely
Please check and let me know what it is. Clip for removing spot

Another clip: Another clip

BTW, I tried Vitamin C. However it didn't do noting. (I saw little bubbling. However I think it is natural reaction with water..)

Thanks.

 

[kimkats]

I think you are correct.

 

[Texas Splash]

Odd. There seems to be a distinct difference between the stains in post # 6 versus post #8. The #6 photos do seem like they could be resulting from something underneath, while the ones in #8 look just like a washer and a hairpin fell in the pool and sat for a bit. Unfortunately from my current computer, my server won't let me go to your links, so I'll have to look at them when I get home. Maybe someone else will reply. If you believe the stuff you scraped to be calcium, you can confirm by collecting it and pouring a little muriatic acid on it. It should frizzle. If it doesn't, it's not calcium.

 

[NewB77777]

Odd. There seems to be a distinct difference between the stains in post # 6 versus post #8. The #6 photos do seem like they could be resulting from something underneath, while the ones in #8 look just like a washer and a hairpin fell in the pool and sat for a bit. Unfortunately from my current computer, my server won't let me go to your links, so I'll have to look at them when I get home. Maybe someone else will reply. If you believe the stuff you scraped to be calcium, you can confirm by collecting it and pouring a little muriatic acid on it. It should frizzle. If it doesn't, it's not calcium.

I poured acid on the powder, and it frizzled.
So, I think it is calcium buildup.

Now, I have questions.
If I scrape, I think I can remove buildup on plaster.
However I wonder if it is possible to remove all mark(black circle shape things)
With just scraping, I count remove the mark.

And If it is calcium buildup, does it mean our plaster already got damaged?

And are there faster way to clean the calcium buildup?

Thanks