yes, you can
Yes, you can DIY, but you'll need big bottles. Try 1 gallon gatorade jugs. At least 2, maybe 3, test and see if you get the pH drop you need before you bother with the 3rd.
You'll be changing bottles pretty rapidly, on different weeks to keep the CO2 constant. It can be done.
Just keep in mind that a pressurized system costs about $90 for the regulator/bubblecounter/solenoid, plus about $70+/- for the tank of CO2 so that is $160, plus some sort of reactor. If you make a power reactor that may cost $10+/-, buy one for $25 to $75, depending.
Just be careful to not nickle and dime yourself to the point where you've wasted money you could have spent on a pressurized system. $10 for silicone, $10 for a different glue when the silicone keeps breaking, $6 for silicone lines, $16 for a pump or power head, it just adds up.
With 90 gallons, you will do better with a pressurized system.
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110G, 10 adult discus, barebottom with plants on wood
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