Whatever you don't loose the second packet
If you want to fill a standard bath tub, even half way with goo buy two boxes. Also, do not loose the dissolving pack! I used two boxes of the red to make a Halloween gag at a friends party. We stuck a skeleton in the goo to look like he dissolved. It looked totally cool and was nice and gooey, but some drunk A-hole stole the dissolving packets. It took forever to get the mess cleaned up. I had to refill the tub repeatedly and use a plunger to get it down.
Reviewed by: Amanda Prescott from SC.