OK I'll bite.....
Soda bottle Co2 is exactly the same as the Hagen setup you're using now. It just doesn't cost $30+ to put the pieces together. If you're happy with what you have the Co2 is helping your plants then you really have no need to worry about a pressurized system. Going pressurized is for larger tanks, ease of use + consistency, and better control. In the end its all doing the same thing, putting Co2 in your water. While your lights are on plants produce oxygen and use Co2 during photosynthesis. So the Co2 you add to the water is getting used. When the lights go off plants use some oxygen and produce Co2. People use solenoids to turn off Co2 injection when lights go off to avoid wasting Co2 since the plants don't use it at night and also to avoid oversaturating the water with Co2 which can be dangerous to fish. There are a million threads on here regarding all these topics in exhaustive detail. I just gave you the highlights. Use the search and just read everything you can. Its the best way to learn on here... good luck.
Soda bottle Co2 is exactly the same as the Hagen setup you're using now. It just doesn't cost $30+ to put the pieces together. If you're happy with what you have the Co2 is helping your plants then you really have no need to worry about a pressurized system. Going pressurized is for larger tanks, ease of use + consistency, and better control. In the end its all doing the same thing, putting Co2 in your water. While your lights are on plants produce oxygen and use Co2 during photosynthesis. So the Co2 you add to the water is getting used. When the lights go off plants use some oxygen and produce Co2. People use solenoids to turn off Co2 injection when lights go off to avoid wasting Co2 since the plants don't use it at night and also to avoid oversaturating the water with Co2 which can be dangerous to fish. There are a million threads on here regarding all these topics in exhaustive detail. I just gave you the highlights. Use the search and just read everything you can. Its the best way to learn on here... good luck.
