black sides on 16ft vinyl pool

Algae problems in swimming pool water.
Green (cloudy) water or slimy pool walls.
Black algae. Mustard algae. Pink or white pool mold.
gmaltese

black sides on 16ft vinyl pool

Postby gmaltese » Sat 28 Aug, 2010 20:00

help i have a 16 ft vinyl pool above ground, saltwater generator, the last few days here in florida it has rained, about 90 plus deg. after that i noticed about one foot wide on the bottom all around the whole outer pool floor/side wall a black grayish stain. i thought it was just the pool liner, then a few days after that the walls from about 2 inch from water line down to bottom a blackish color, tryed scrubbing no luck, it looks like a stain, if i uses my finger nail and rub it about 30 seconds the black goes a way and i see the nice blue liner.but thats just 1 2x2 in square there are lots of squares. i think its black algae.
my queston if i shock and add algaeside how long un till this clears up, by the way before i stared scrubbing the water was crystal clear now a very very lite green look to it, and every 4 hours or so the bottom of the pool has a pile of what looks like a gray powder dirt. i vacuume and the piles comes back. it has only been about 12 hours since i started the clean up. :?
thanks


duraleigh
Swimming Pool Wizard
Swimming Pool Wizard
Posts: 81
Joined: Sat 07 Aug, 2010 23:26
My Pool: 24X52 DIY Concrete and liner
Location: Raleigh NC

black sides on 16ft vinyl pool

Postby duraleigh » Sun 29 Aug, 2010 10:13

If you can post a full set of test results it will be helpful in getting your pool cleared up.

However, I can be fairly safe in saying you have had inadequate chlorine levels in your pool and will need to elevate and hold those chlorine levels until; your pool clears.

Regardless of the type of algae (it's almost surely not black algae in a vinyl pool), the treatment will still be the same.....elevate you chlorine over a period of time.

Just how high to elevate the chlorine can be determined by your current test results.
24x52 DIY concrete block and liner
1.5HP pump 925lb sand filter
http://www.tftestkits.net
gmaltese

black sides on 16ft vinyl pool

Postby gmaltese » Sun 29 Aug, 2010 11:40

duraleigh wrote:If you can post a full set of test results it will be helpful in getting your pool cleared up.

However, I can be fairly safe in saying you have had inadequate chlorine levels in your pool and will need to elevate and hold those chlorine levels until; your pool clears.

Regardless of the type of algae (it's almost surely not black algae in a vinyl pool), the treatment will still be the same.....elevate you chlorine over a period of time.

Just how high to elevate the chlorine can be determined by your current test results.


thanks , nice to know its not black algae, when this happened the cl was between .6-1 ppm
the ph was at 7.8 and the cooper level was .1 ppm sorry but thats the only three things i ck.
only had pool for about 2 months i have shocked the pool 10 ppm cl and put in an algaeside ph still at 7.8 seems some what better have been scrubing the sides about every 8 hours.
duraleigh
Swimming Pool Wizard
Swimming Pool Wizard
Posts: 81
Joined: Sat 07 Aug, 2010 23:26
My Pool: 24X52 DIY Concrete and liner
Location: Raleigh NC

black sides on 16ft vinyl pool

Postby duraleigh » Sun 29 Aug, 2010 15:45

Well, I would really like to see your CYA test result but without that, i can make a guess on your FC level.

I would suggest you bring the FC level back to 10ppm and then HOLD IT THERE 24/7 UNTIL THE STAINS GO AWAY. To hold it there you must recheck the FC level twice daily and add enough to get back to 10ppm each time. Brush the stains as often as you can and backwash/clean the filter as necessary.

Now, here's the rub, without that CYA test result, I can't tell if that FC level is nearly enough....you may need 20-30ppm FC based on your CYA level but you don't want to put that much in there if you have no CYA at all.

See if you can get that tested and post back.
24x52 DIY concrete block and liner
1.5HP pump 925lb sand filter
http://www.tftestkits.net
gmaltese

black sides on 16ft vinyl pool

Postby gmaltese » Sun 29 Aug, 2010 16:21

duraleigh wrote:Well, I would really like to see your CYA test result but without that, i can make a guess on your FC level.

I would suggest you bring the FC level back to 10ppm and then HOLD IT THERE 24/7 UNTIL THE STAINS GO AWAY. To hold it there you must recheck the FC level twice daily and add enough to get back to 10ppm each time. Brush the stains as often as you can and backwash/clean the filter as necessary.

Now, here's the rub, without that CYA test result, I can't tell if that FC level is nearly enough....you may need 20-30ppm FC based on your CYA level but you don't want to put that much in there if you have no CYA at all.

See if you can get that tested and post back.


hello my wife told me to try white vinagar on a spoonge so i did and the blackish stains that i put the spoong on with in seconds were gone.grant it was about 6 inchs underwater, i do have another question,
can i pour white vinagar in to pool, or is there something that is like that, that is safer.have you ever heard of any one using white vinager in this manner? thanks glen
James Watson

black sides on 16ft vinyl pool

Postby James Watson » Sun 29 Aug, 2010 16:27

and the cooper level was .1 ppm sorry but thats the only three things i ck.

Does your chlorinator also add copper? If it does, then that is not good. You should stop using copper. The black stain could be from the copper. It could be Copper (II) oxide aka cupric oxide (CuO).
http://aquamagazine.com/articles/articl ... &zoneid=13

Get some ascorbic acid and put it on the stain to see if the stain goes away.

It could also possibly be from vandalism. Is there a chance that anyone threw anything into the pool? I'm thinking like charcoal ashes, or something like that.
James Watson

black sides on 16ft vinyl pool

Postby James Watson » Sun 29 Aug, 2010 16:37

water was crystal clear now a very very lite green look to it,

Probably due to the high copper. Stop adding copper.

i have shocked the pool 10 ppm cl and put in an algaecide

What did you use to shock the pool?
What were the ingredients in the algaecide? Did the algaecide contain copper?

OK, I just saw that you tried vinegar and the stain went away. That indicates that it is most likely copper. Lower the pH to about 7.2 to see if that will help. Add a sequestrant to help keep the copper from staining.
gmaltese

black sides on 16ft vinyl pool

Postby gmaltese » Sun 29 Aug, 2010 17:15

James Watson wrote:
water was crystal clear now a very very lite green look to it,

Probably due to the high copper. Stop adding copper.

i have shocked the pool 10 ppm cl and put in an algaecide

What did you use to shock the pool?
What were the ingredients in the algaecide? Did the algaecide contain copper?

OK, I just saw that you tried vinegar and the stain went away. That indicates that it is most likely copper. Lower the pH to about 7.2 to see if that will help. Add a sequestrant to help keep the copper from staining.



i think you guys are on the right track, i do have a copper clorinator, im going to drop the ph down to 7.2 and allso get a beter pool tester tomarrow. ill let you guys know what happens in the next few days... thanks alot. glen :)
James Watson

black sides on 16ft vinyl pool

Postby James Watson » Sun 29 Aug, 2010 17:40

I also advise against shocking the pool. Shocking will only make things worse. Maintain a good, but not high, chlorine level. Add some 60 % PolyQuat algaecide to help prevent algae while trying to clear this up.

Some of the salt chlorinators with copper ionizer, like the Intex, will add more copper when using "Boost" mode. Therefore, you do not want to use boost mode. You should disable the copper ionizer, if you can figure out how to do that without ruining your unit or voiding the warranty.

You might need to do an ascorbic acid treatment if lowering the pH does not work.
duraleigh
Swimming Pool Wizard
Swimming Pool Wizard
Posts: 81
Joined: Sat 07 Aug, 2010 23:26
My Pool: 24X52 DIY Concrete and liner
Location: Raleigh NC

black sides on 16ft vinyl pool

Postby duraleigh » Sun 29 Aug, 2010 21:11

Before you treat for copper, I would suggest testing for copper. Your description in your initial post seems to imply the stain appeared very quickly, which would not be indicative of a metal stain.

Nevertheless, Shocking will not help a pool with metal stains so you've gotten good advice to hold on that. If your copper tests higher than .3ppm and your pH has been high, then that may well be the cause.

Can you post a pic of the stain?
24x52 DIY concrete block and liner
1.5HP pump 925lb sand filter
http://www.tftestkits.net
James Watson

black sides on 16ft vinyl pool

Postby James Watson » Sun 29 Aug, 2010 21:40

Duraleigh, the poster has a copper ionizer.

The copper might test low now because most of the copper is now in the form of a stain.

The copper was probably high when they shocked the pool and this could cause the type of staining they are reporting. This type of stain can appear suddenly under the right conditions.

The poster reports that the stain went away when exposed to acid. This helps confirm a diagnoses of copper stains.

The poster should get some ascorbic acid to test a spot to see what effect it has.

Return to “Pool Algae & Green Pool Water”

Who is online at the Pool Help Forum

Users browsing this forum: No registered users and 7 guests