Putting a bad idea to a good use.
I've been running a DIY setup for a few years now. Until recently, I just ran the supply tube into the suction line of a power filter. However, I recently added more light (3watts /gallon), and the old system could not keep up. I switched from a power filter to a 2013 cannister. It came with a spray bar. You will hear many people talk about how bad a spray bar is for a plantedd tank, and they are right When installed according to directions, it churns up the surface of the water, causing te CO2 to disipate rapidly. Kinda like shaking a soda. Instead, I ran the outlet of pressure tube to the bottom of the tank. I then mounted the spray bar with the wholes facing down along the back wall of the tank right there at the bottom. Next I drilled a hole for the co2 supply line in the silicone tubing just before it enters the spray bar. Now the pressurize water stream blasts the CO2 bubble to smitherenes, and shoots the mini bubble toward the bottom of the tank. No those little bubbles have to reverse direction before they can rise to the top. Most of them never make it. They are completely absorbed before they reach the top. The current from the spray bar does not disturb the surface of the tank at all and the water movement below the surface improved the ability of the plants to take in nutrients. My CO2 now hovers in the 40ppm range.
Also, I have never had a problem with to much CO2 from a DIY bottle system. Of course my old system was so inefficient that it was not a problem. On the other hand, with 1.5 watts per gallon, of light, I didn't need such an efficient system.
Good luck. My advice is to try to keep this simple and beef up your system only if you see it is necessary. Of course that strategy fits my personality, it is just as likely to drive another guy crazy. There is something to be said for designing it right the first time.