murky green water

Please help, I'm perplexed!! I have an intex 5000 gallon pool with a 1hp hayward 150lb sand filter. I know the filtration is overkill, but I have metal problems in my water and I bought the filter secondhand.

After filling the pool from the hose, the water was tinted green, but crystal clear. I added a phosphate free metal sequestrate that didn't work, so I added a phosphate based sequestrate, which also didn't seem to get the green tint away. Finally I raised the pH, which was at 7.0, to 7.6. This, coincidentally or not, turned the pool blue. A week after having the pool blue, the sequestrate that I didn't think was working apparently started to separate because I began seeing rust at the bottom of the pool that was evidently turning the water green again. After adding more phospate free and phosphate based sequestrate the pool was still green.

In the meanwhile my CYA was on the low side - under 30, but holding chlorine. Several times I added a gallon of bleach, but to no change in the color. In fact, the green-ness is now at it's worst - murky and thick. Yesterday at 3:00 I added a gallon of bleach, and almost 24 hours later the FC reading is 3.5, which though my CYA is low, I think is relatively holding well.

Another thing that is baffling me is the pH. I've done several readings and found the level to be 8.0, which I tried lowering (several times) with Dry Acid. I used the Taylor kit to determine how much I needed to lower it, but it's still reading 8.0. In, addition to that when I went to the pool store to test the pH, one store got a reading of 7.6 and another store got a reading of 6.8. I don't know which reading to believe!! Can the pH be making the pool murky green.

CC is 0
TA 80-85
Calcium (though I know it's irrelevant in a vinyl pool) is 500.

One pool store said my iron is 0, which I find hard to believe based on the rust. Could be copper?

I'm at my wits end. Why is the pool murky green?! The walls are NOT slimy!!

Anyone?

I would trust my own readings over those of the pool store. The green is not caused from the pH. What is your CYA level? The calcium is very high. You are right that a vinyl pool does not need calcium and a low calcium reading is a non-issue, but a high calcium reading can be an issue and cause cloudy water. I don't know if your problem is a combination of cloudiness from the calcium plus an algae mess or what. Cloudy and green is usually algae and cloudy and clear is usually a metals problem.

Don't add any more pool store products. Try the pH test again when the chlorine level is not high. You say that the walls are not slimy, but is the floor?

Also, can you test your chlorine tonight after the sun is down, and test again in the morning before the sun hits the pool, and tell us both those readings?

did you get your problem resolved?