1. Start adding PLAIN 6% household bleach at the rate of 2 gallons (or (3) 96oz jugs ) each EVENING. Filter / pump on 24/7
2. See if you can get the HTH 6-way kit at your Walmart (check availability)
3. If not, get a cheap OTO/phenol red testkit.
4. Add bleach doses EVERY evening, unless OTO shows DARK yellow.
5. Brush the pool completely at least every other day.

Here's an idea of what to look for: Photo-resurrection-Baquacil-conversion-in-summer-2004

6. Once the WATER is done, replace the sand in your filter.
7. Begin adding stabilizer.