I’ve seen many posts and builds about paintball setups for aquascaping. But, I’ve never found one that gave me a budget option when setting up CO2 aquarium (aside from DIY) and let alone from a single aquarium supplies store online (Amazon in this case).
When attaching your check valve, you’ll want to make sure you do it right. Because you are essentially protecting your hardware, in many cases an air pump or even more expensive…your solenoid/regulator for CO2.
When choosing your light fixture be sure to be aware of your plant placements. In your planted tank, you’ll want to have every single plant exposed to some form of light, whether indirect or not. Typically, an LED aquarium light bar that covers the entire length of your tank should be good enough and if you have an island-style scape, a full spectrum spotlight will work just fine.