Hello, this is my first grow. And i want ask a ser...

So basically it goes like this plants "like" a fresh air exchange( its not needed plants dont breath oxygen they breath cabon dioxide) a fresh exchange of air is optimum for growth flowering and so on (the co2 in the air eventually gets used up this is why exchange of air is important) its very doable without if you have the right equipment but simply being able to add fresh air from an open window to you're grow room for the plants to use is enough . The C02 system works well when the heats are high it helps the plant to be able to breath through it . Alternatively you can just open the window 2-3-4-5 times a day as needed to add fresh air . I hope this helps you understand a bit better about air flow and ventilation as well as optimum times to use a C02 system . -Happy Growing!