So here is what I did Ductaped bird feeder protector wrap (petco) around the filter output and leave an inch or more inside the water , Now you have controlled fluctuation still giving you minor aeration , which means you dont have to worry abotu gassing your fish if you have a low plant load atm.
As for Conserving DIY co2, if you live anywhere thats not below freezing at night, you can keep your DIY co2 setup contraption outside, at the lowest temp here in california at night, the DIY setup slows down to like one bubble every 3 secs. What this picture shows is how I bring it up to speed again. I have a bucket of water that I keep a heater in. I drop the mixture bottle inside the bucket and literally 15 mins later im back to 2pbs again. This stays constant throughout the day.
Also I use a hard liquor yeast and I feed it sugar and a home made nutrient which consists of a frozen ice cube of bread yeast killed in boiling lemon juice. 1 cube a liter of solution works great for me.