Can you take the Bioguard back? Bleach will work. Do you have any idea what your CYA reading was upon closing in the fall? If you had some when you closed and now have none upon opening, then what you are experiencing is what happens to a lot of pools over the winter. We see this every spring. As Ben likes to explain it, bacteria "eat" the CYA and then "poop" out ammonia and it takes a LOT of chlorine to break down all the ammonia. We have lots of threads currently going where other people are dealing with this same problem.

If this is what happened, then you may have had an algae bloom in the works due to chlorine that was too low. Either way, the remedy is the same. Patience and a lot of bleach.

At any rate, I hope you get your kit soon so you can quit relying on pool stores who are there to make money. They love to sell impatient people products that they think will hurry the process along. It usually does nothing more than make the pool store cash register full, your wallet empty and often causes more problems in your pool.

Keep adding bleach. At some point, it will hold.