This is a CO2 cylinder that’s certified and already filled with CO2.
You will need a CO2 regulator to use this for your aquariums.
SEE HERE -> CO2 Regulators
We do not refill CO2 cylinders at our store, we buy and re-sale from Soda Mistic .
You can visit there location(s) to refill or purchase cylinders directly.
Only logged in customers who have purchased this product may leave a review.