ive just set up a 120l tank to re home the SAEs from my high tec, so i can grow some moss. the tank has 2 x t8 tubes over it, both 2' like the tank. my nanos giving me the hump so if its worth braking it down and putting co2 in the 120 . to have a low light high tec set up.will the co2 make a difference for example will carpeting plants grow under these condition's. or is adding the co2 a waste of time. id quite like a carpet but don't really want to up the lights. im sure ive read that high light is not need if co2 and flow are good. 2x fluval 205s if i brake down the nano. and cat litter and gravel substrate.