By going overboard in the doseage, you're still okay and won't really notice an appreciable rise in your salt level. 11 gallons would take it up to 26-27 ppm. You just don't want to go too high in a vinyl pool and risk fading your liner.

Adding bleach in the evening is probably when you'll get the best bang for your buck, because it doesn't have to compete with the sun, but the key to clearing up the green is going to be consistency in keeping it above 20 ppm.

Janet