im on a first grow. i do spray with soda water. i put the srew on pump thing from my water spray bottle,..just screw it onto your soda bottle and spray. prob is,..in the spray process,...you lose a ton of co2. i notice after just a few sprays,..the water comes out bubbleless. heres a cool trick. pour the soda water str8 into your soil. it has a cool effecet. it acually loosens the compact soil,..allows air into the dirt/root system. it will actually lift the level of the dirt and become airy/fluffy to the touch. you actually need to push the soil down a little,...it breaks it up,..airs it out that much. today i discovered this. my plants look awsome.