Hello from another newbie to BBB.
I have a 16 x 24 oval above ground pool with a sand filter. We have been using Softswim the past 2 summers. First year was fine, 2nd year was cloudy all summer and this year we opened with algae... so I found this and decided to convert. My well water is extremely hard so we use a water softener inside. After a week of following the instructions (started 6-14-14), adding tons of bleach, backwashing, scrubbing sides and cleaning regularly, the pool went through the gross stages and is now looking good, with the exception of remaining cloudiness. (I only had the simple tester and kept the cholorine a bright orange.) I finally got the good test kit yesterday (Taylor K 2006) and these are the numbers (first time so not sure how accurate?)

TC 3
FC 1
CC 2

TA 250
CH 575 (don't need this in a vinyl pool?)
PH 7.8
CYA ?(I tested once but was not cloudy so not sure if I did it right. Thought I'd check in before testing again)

We were gone for the weekend and I left "floaters" made from half-filled bleach bottles with a slits cut to "leach out". It obviously did not keep the shock level high enough

When putting these numbers in the pool calculator, it said to add muriatic acid and more bleach, which I will do this morning. It also said to replace 55% of the pool water! Really? Considering my hard water, I don't think that will help much.

The other factor is my filter. It was new last year and I added new sand. However, we get a lot of debris from trees, bugs, etc. and it looked really dirty this spring. I rinsed it well before starting it up, knowing I would need to replace the sand after conversion anyway. So, the new sand is ready and waiting until the water clears up.

Here are my questions:
1. What is probably causing the cloudiness? Hard water? Dirty filter? Not high enough shock level consistently?
2. Why does my PH read normal when the TA is so high?
3. What is my next step? If I add acid to adjust the PH and TA, will that delay the process of clearing or help?
4. CYA-Why is it non-existent and should I be adding some? I bought some last week. Since the tri-clor tabs have some CYA in them, would it be feasible to get some to keep it consistent?
5. Should I go ahead and change the sand so the filter works more efficiently, or would I have to change it again after it clears?

Everything I had read says to just use bleach and lots of it, but it seems adjustments need to be made. I'm just not sure the best plan of action at this point. I was hoping we would return from our trip to sparking water, but... not meant to be. Any help would be appreciated. Thank you!