When using CO2 you must have a cover on the tank and avoid using accessories which mix air into the water (the plants add plenty of oxygen to the water), as the dissolved CO2 levels will fall quickly.
(the dissolved CO2 levels; will fall quickly; ) (you; avoid; using accessories which mix air into the water; T:When using CO2) Context(you avoid,List([15, 58))):(you; avoid using; accessories) (the plants; add; plenty of oxygen; to the water) Context(the plants add,List([107, 121))):(you; must have; a cover on the tank; T:When using CO2)
you avoid,List([15, 58)) the plants add,List([107, 121))
the dissolved CO2 levels you you the plants you
will fall quickly avoid avoid using add must have
using accessories which mix air into the water T:When using CO2
accessories
plenty of oxygen to the water
a cover on the tank T:When using CO2