Newbie just beginning to understand "free" and "total" chlorine. . .

[waterbear]

No only will it help the cell live longer, it will indirectly give you better pH stability. It's a lengthy explanation that I won't go into now but once things slow down in the fall I will be glad to explain it!

Also, as a rule of thumb you want to keep your FC at 10% of your CYA level (as a minimum) or a bit higher for a margin of safety.
Order the K-2006 and do your own testing. Pool store testing is often suspect (I know this first hand, having worked in pool stores!)

Iron in your water can cause the water to turn yellow and can casue yellow to orange stains...combine that with a blue liner and you have your greenish color. Using a metal remover on a regular basis is the right thing to do but you want to use one that is HEDP. Many of the 'metal remover' products are blends or ineffective chamicals such as EDTA that break down quidkly in the presense of chlorine so they do not do much good at all. Exactly what brand of metal remover did they sell you?
If you prefer you can get this one from Amazon, it IS HEDP:

KemTek 20% HEDP @ Amazon

You want to use the initial dose of 1 oz per 1000 gallons (for your pool 2 quarts) and then a maintenance dose of 1/4 that amount ever week or two of HEDP.