Preface of this test:
My well doesn't have high iron, but I have copper piping in the house. Previous owners used copper based algaecide and I've always had yellowish stains on the sloping surface of the deep end with some darker stains on the vertical sidewalls. I did a direct ascorbic acid treatment 2 weeks ago with no sequestrant, it removed the vast majority of unsightly stains, so I don't always think there's a bloom a coming.
I know there is a bit of "hive mentality" here in that the only way to remove metals is through a drain&refill with metal free water. I've used this similar setup in many industrial applications for reduction of free metal ions (on a larger scale) with success so why not try it on the pool.
Two Dupont filter housings plumbed post sand filter. First has a 5micron filter, second a charcoal filter. Timed bucket test ~5gpm on new filters with backpressure from the eyeballs.
I added an extra valve off the Tee on the left for a future fill hose connection.
Eliminated any copper end hose connections as I noted some copper precipitate inside the existing fill hose.
Simple DIY project, total cost of materials ~$125, including an extra set of filters. Filter housings can be sourced for cheaper money online, these were $33/each at walmart(with tax)
Note how much metal scale was found in the 2" section cut for the 1.5" tee