m0useanswered grow question 3 years ago They are more of a fire hazard if anything.
and when the wax burns they are producing more then c02 from the combustion.
Not worth the risk.
You only need c02 with all other environmentals are in check.
Its more for pro growers, same with lighting setups with over 900 PPFD
The better method for co2 is the fungus grow bags, ExHale CO2 Bags.
Good Luck!