It's a little more complicated than that, unfortunately.

When the iron is 'green', it's usually in a soluble (dissolved) state, and cannot be filtered. It can be "adsorbed" onto various zeolites, like the CuLator product . . . but this is a very slow process.

So, the usually way by which metal leaves a pool is when it becomes insoluble. This is what happens when it 'stains' various surfaces. It can also form iron oxide (or other iron salt) particles, which can settle to the pool bottom, or can be filtered out.

What makes it even more complex is that not all 'green' iron is alike. I have worked with well water that would come in green but very clear, and would INSTANTLY turn orange when you added chlorine. But I've also worked with 'green' water that would only very slowly oxidize to the insoluble state.

So, just saying that there's "iron in the water" doesn't really tell us what you'll be dealing with . . . and thus makes it really hard to give a recipe or prescription. The steps I gave you above, will usually work, in a fairly reasonable time. Especially if you use the polyquat, you CAN swim, while you are cleaning up iron.