You may will need more CYA, but that's not necessarily your problem. Do this:

1. Add 4 gallons of bleach in the EVENING; then test in the MORNING.
(That will tell us whether you are losing chlorine to sunlight, or something else!)

2. Order a K2006 (or K2006C).
(You can use the Amazon link in my signature. The K2006C tests 3x as much water, but only costs 1.5x what the K2006 does)

3. Tell us what sort of pump / filter / piping / equipment you have.

4. Send equipment pictures (if possible) to poolforum@gmail.com

5. Tell us what your CYA level was last fall.