Need help - stains on bottom of pool, turned GREEN right after shocking

[zoeybanana]

Inground pool, DE Filter - 25,000 gallons, vinyl liner.
Noticed staining on bottom of deep end about 4 weeks ago. Shocked and shocked, swept and swept with the broom, did not come up (brown-ish stains). I was told it could be mustard algae and sold a chemical to treat it. didnt work... went to another place for a second opinion - tested my water, all levels were good. They sold me Super Erace assuming the stains were metal related. I put that in last Friday as instructed and the pool was very clear but the brown stains remained. They concluded that it was mold under the pool liner and I needed to completely replace the liner.
I just shocked the pool because some green was forming in the corners and walls (3 pounds of shock) and the pool almost IMMEDIATELY turned lime green and slightly cloudy. After some research, it looks like this could be metal related? I have never ever had this problem before. If you could help me with what to do next, that would be so helpful. The stores are not helpful. This "green" after shock leads me to believe that the stains are metal stains maybe?

[Watermom]

Green that appears when shocked typically means metals. What is the source of your fill water? What kind of chemical did you add to treat the mustard algae?

Also please list all products you have added to the pool meaning ingredients, please, and not just product names.

Welcome to the Pool Forum!

[zoeybanana]

Thanks for your quick reply.
Morning update - pool is clear as a whistle. DE filter filtered all the green out over night apparently. Stains on bottom of pool remain.
Source of pool water - well water. I have had the pool for years and years, no metal issues. Whenever pool gets low, which is happening often lately, I fill with hose water (well water).
When I went in for the stain initially, they sold me "Green Away" - which is like a super duper shock apparently... I will call the store when they open and see what the ingredientas are exactly.
A week later, I went to another place because of stain. They assured me it was NEVER mustard algae because that algae is easy to brush off and this stain was not moving with brushing. They checked my water - everything good for treatment - sold me Phoenix Super Erace (Highly concentrated formula removes sequestering and chelating metals (iron, copper, manganese), removes metal stains, restores water clarity as well as reduces scale formation on pumps and heaters. Super Erace works by forming a clear insoluble crystal with the metal ions normally found in the pool. These insoluble crystals are then removed by filtration) http://phoenixproductsco.com/metal.cfm
When I shock, I use 3 lbs of HTH Super Shock.
I am hoping and praying that the staining on bottom of pool is metal related and not mold... does the green after shocking signify to you that it is metal related?

[Watermom]

does the green after shocking signify to you that it is metal related?
That is a pretty good indicator.

[zoeybanana]

So your thoughts are with this info and history that the stains on the bottom of the pool are metal related (not mold)?
If so, what route do you suggest I take now? I really want to clear up this problem before it is time to close (<1 month). Any suggestions for getting rid of these stubborn stains?

[BigDave]

Put a couple vitamin C tablets on the stain and let them stay a day or so. If the stainlifts under the tabs, it's metal and can be lifted by ascorbic acid treatment (check back for specific instructions).
Put a couple small pieces of a trichlor tab on another stain and wait a while. If the stain lifts under the trichlor then it's probably organic and can be treated by high chlorine.

[zoeybanana]

Thank you for the suggestion.. how can I accomplish that in a deep end of the pool?
I was advised by the pool place to scrub with baking soda in a sock... same type of thing? Do I get these Vitamin C tabs at the pool store?

[BigDave]

I don't know about baking soda in a sock. Vitamin C - grocery, pharmacy, etc. Trichlor tabs are a pool store item, some places they're sold one at a time.

[zoeybanana]

Here are a couple pictures of the staining. I will try the baking soda test this weekend and get water tested too. Wondering your thoughts on the appearance of this stain. Water is shocked and pool completely vacuumed.
https://mygoodoldhouse.files.wordpress.com/2014/08/photo-1.jpg
https://mygoodoldhouse.files.wordpress.com/2014/08/photo-2.jpg
https://mygoodoldhouse.files.wordpress.com/2014/08/photo-3.jpg

http://mygoodoldhouse.wordpress.com/2014/08/08/pool/