Do NOT spray your plants with seltzer water.
Also you are only ferting every 4 weeks.
Fill out the form and post pics, but it sounds like the plants are hungry.

BTW yellowing is not the first symptom of rootbound. It's under-curled or slightly cupped leaves, and evidence that soil chemistry is starting to fluctuate. You'd see metals lockouts before general yellowing. General yellowing is typically N and/or Ca def or overheating of the space to 95 degrees for a sustained period of time.