Stains - Can I Clean?

[danrheath]

I have an in ground diamond brite pool 4-5ft, built 1997. Bought the house a year ago and it had these stain on the bottom. I think the old lady let it go for a bit. I have been following the rules and have only had 1 bout of yellow algea that will killed fast.
Any way to get rid of these stains? They dont brush. I'm trying to avoid getting it redone.

 

[Azgirl71]

I am not certain, but it could be iron stains.

Pool School - Metals in the Water and Metal Stains

 

[danrheath]

They are brownish

 

[jblizzle]

Do they feel raises/rough? If so, could be calcium scaling ... test results?

 

[danrheath]

Not raised. Its pouring rain now, will do vitamin c test when it stops.
Did notice that well water can cause it on stains, pool was filled/topped off with well water.

 

[Divin Dave]

Im with jblizzle, leaning towards calcium.
This can happens when the pH isnt kept in check.

If its calcium, the only real remedy is drain and acid wash.

If the vitamin C dont work, then rub a chlornine puck on a small spot and see if the stain lightens or disapears.
If it does, the stains are organic in nature and raising FC to SLAM level and Keeping It There until stains are gone will do the trick

If the vitamin C does the trick, then Ascorbic Acid treatment will fix it.