Why do people end up using CO2?
a)Because they have ,or want to have lush vegetation(hey ,that plant looks cool ,I want to have that too!)
b)Because they want to have Big plants?
c)Because their plants don't grow healthy?
d)Because they have algae and think it will solve the problem?
e)Because they want a nice green carpet ,like they saw on internet pictures?
f)Because they read it helps with general plant growth?
g)Because the neighbor is using it ,and his tank looks way better?
h)Because they want to grow demanding plants and take the scape to some expo?
i)Because they got the latest LED hood and they need to keep up with it?
j)Because the LFS told him so?
k)Because the fine bubbles coming out the diffuser look cool and professional?
l)Because they think they are so far out in the hobby ,they need to try something new?
m)Because they measured with the latest infrared macrochip CO2 scanner and think they need more?
n)Because they read a lot about fishkeeping and aquascapes and they are confident about what they are doing?
o)Because it can't hurt?
p)Because plants really need it?
q)Because they bought the latest most complete fertiliser and need CO2 to get better absorbtion from plants?
This is all rhetorical ,conceived after a couple of beers.Feel free to add more if so you wish.
Can't come to work today ,Boss......I've got Bolbitis...