Co2 Cylinder?

[21rm]

Ive seen some people ere have bought co2 cylinders for their tanks, but was wondering are they necessary. I have a planted tank and my plats seem to grow ok without the extra Co2

 

[aaronnorth]

if it isnt broke, dont fix it

CO2 inly becomes necassary with high lighting,

 

[21rm]

thats very true lol
thanks