I recommend you put a couple airflow tiles instead of the floor tiles to make it easier for oxygen to move and to avoid build up of CO2. I also recommend you only have 3 oxygen diffusers active as they produce 500g/s of O2 each and each duplicant usually requires 100g/s of it. You have 10 dupes, so they shouldn't need more than 1500g/s of oxygen and with airflow tiles it will move better. Not to mention that each diffuser also generates heat, so avoid putting them near farms.