CO2 is important for maintaining constant pH in cell culture. Unfortunately, I do not have access to such incubator and buying a new one is expensive. I found a cheap incubator online, but it doesn't support CO2. I'd like to ask if I can cultivate cheek epithelial cells in such incubator and if it won't negatively affect my cell culture. Another option is building a small CO2 generator inside the incubator. I made some calculations - I know how much CO2 I need to generate, how many grams and mL of solutions I need, moreover the build-up pressure is so small, it should not negatively affect the incubator.