Fill your trichlor floater with pucks and tie it to two sides of the pool so it stays pretty much in the middle. Dose the water with bleach to 15-20 ppm. Run the pump at night if your timer lets you make that setting, 6 hours should be plenty of time. If you have an opaque cover, put that on to help keep out sunlight. The trichlor will drop the pH some so be ready to raise that when you get back home, and have some bleach on hand to pour in after you return.

Have a great time on vacation! Don't give the pool another thought. Remember: you KNOW how to fix a green pool.