[How Do I Remove Staining On A Blue Fiberglass Pool?]

Yup pretty sure they use lamothe by what you describe.

 

My salt cell is IC20, I have not tried liquid chlorine yet, neither at open, was powder shock then added stabilizer in sock.

For the stain removal its only been a liquid one that targets metal.

 

I have the cell still running at 100% and will test water at pool store again tomorrow.  

[How Do I Remove Staining On A Blue Fiberglass Pool?]

On 6/18/2020 at 12:03 PM, Rizzil said:

many thanks both of you, the pool is fiberglass and brown and ring shaped, so your saying could be cobalt and very hard to remove?  (we dont use well water just city water)

Going forward will order the testing kit and keep water stabilized.

Hopefully once water stabilized for a couple weeks can tackle the stains, will also get a picture to upload for you.

 

On 6/18/2020 at 10:48 AM, waterbear said:

You said that the stains were brown and ring shaped. It could be cobalt spotting, which is only a problem in fiberglass pools and very difficult to remove. It could also be manganese, which often stains fiberglass a brownish black and is also difficult to remove. Cobalt spotting is caused by water chemistry that is out of whack, manganese is usually from water used to fill the pool (most often well water). Most metal stains occur when pH is very high, as yours ism which causes the metal to precipitate out and deposit as stain.

First step is get your water balanced and keep it balanced! This will help keep any further staining at bay.

Second is make sure your chlorine sources do not contain copper! (Read the ingredients)

Third, get a good test kit (Taylor K2006, not the Taylor k2005) and start testing your own water. Should be done a minimum of weekly if not more often if there is a problem.

Metal stains do not really occur in properly balanced water. Iron staining in a fiberglass pool usually looks like a brown discoloration that covers the entire pool that is underwater and the fiberglass above the water line does not show the discoloration. Running a pool heater will not cause metal staining unless your heater has a copper heat exchanger and your pH is running very low. Copper stains are usually black in a fiberglass pool but can be bluish green or metallic copper colored on occasion. Calcium (which is also a metal) can deposit as scale, a white to tan stain that can feel rough to the touch, when water is not kept in balance.

Sequestrant will not remove stains but will keep metals in water from depositing as stain but you still need to keep your water chemistry in line or the won't work. Only way to get rid of metals in the water is to get them to deposit out as stain. There is a way to get them to depsoit on the filter medium and therefore be removed by changing the filter (sand, DE, or cart) but it requires really understanding pool water chemistry and knowing exactly what you are doing so I won't even go into it.

Good news is that some staining will resolve to a certain extent if you get your water balanced and keep it balanced with no further action. Once that is done you can revisit the stains after a few months of proper water chemistry.

As far as the pool heater it's immaterial as long as your pH has not dropped dangerously low. I keep my pool at 88 degrees year round and pool is open year round (North Florida) Heater doesn't run for a short period during summer when temps are in the 90s and I also have a fiberglass pool.

 

Hope I gave you a starting point, which is to get your water balanced and start testing your own water with a good test kit (Taylor k2006, worth every penny!) https://www.taylortechnologies.com/en/page/231/k-2006-complete-kit-with-fas-dpd

Think of testing your pool water like checking the gauges on your car. You don't take your car to the garage for them to check if your gas tank is empty or if the oil is low. You look at the dashboard and then take appropriate action. Some things you can do yourself, like add fuel or oil (think chlorine), some things require professional attention (high CYA, which requires multiple partial drain and refill cycles and switching to an unstabilized chlorine source to prevent further cyanuric acid increase). Testing your pool water yourself regularly will allow you to keep your FC and pH in line and deal with TA, CH, and CYA when they are out of line.

Ok here's my updated numbers, starting to think salt cell is dead, also now that water clearer, this ring stains look almost golden, brown, yellow.  

What was done to get these numbers was PH reducer, then powder shock then stabilizer, and salt cell running at 100% for 48hrs.  

FC 0.26

TC 0.56

CC 0.3

PH 7.4

Hardness 221

Alkalinity 96

CYA 50

Copper 0.2

Iron 0.2

Salt 3246

 

I will need a gopro to get you guys pics of stains.

[How Do I Remove Staining On A Blue Fiberglass Pool?]

many thanks both of you, the pool is fiberglass and brown and ring shaped, so your saying could be cobalt and very hard to remove?  (we dont use well water just city water)

Going forward will order the testing kit and keep water stabilized.

Hopefully once water stabilized for a couple weeks can tackle the stains, will also get a picture to upload for you.

[How Do I Remove Staining On A Blue Fiberglass Pool?]

Hey Spaguy, just got the test results from the Pool store, also Vitamin C does not work on these stains, tried multiple time rubbing the vitamin onto the stain, it doesn't even lighten up.  (also tried Chlorine Puck over stain nothing, and even these pouches they sell at pool store for stains and no result)

Free Chlorine 0.33
Total Chlorine 2.06
Combined Chlorine 1.73
PH 8.1
Hardness 202
Alkalinity 121
Cyanuric 8
Copper 0.2
Iron 0.1

Also pool heater is on alot, wife like water hot, so must be metal staining, these stains are all from last year when I wasn't using a metal sequestor every 2 weeks.  (since then no new stains)

 

[How Do I Remove Staining On A Blue Fiberglass Pool?]

Waterbear, i had same issue as above however vitamin C did not remove the stains.  In fact nothing from pool store removes the stains.  Ive been using metal sequester weekly and that has prevented new stains.  But they look like rust rings however vitamin c does not remove them.  Any suggestions?