Help with these stains

[rizzil]

See attached the pics, I've tried every solution the pool store has offered, vitamin c, different stain removers for organic or metal and nothing takes these off.

Hoping someone might recognize what type of stain it is, the pool is fiberglass san juan.

There so much more expertise on this board vs our local pool store, really appreciate any comments, thanks.

 

[kimkats]

When you did the vit. C how did you do it? Have you tried putting a chlorine tablet on it? Can you list what stuff you have tried so we can dial in our ideas?

Can you feel the stains? As in rubbing your finger nail over it. Is it raised?

Do you have many trees or bushes around that are putting stuff in the pool?

 

[Texas Splash]

Since you have a FG pool, I would also consider posting a full set of test results so we can evaluate any other potential staining issues (i.e. cobalt stains).