Yea, Finally beefed up the filter / fan / muffler tonight. you know the final tape and seal. Checked the temps and they are up by 2 degrees....runs 69 at night 72 day w/ 40-55% RH. Like the 400 and it works well for one plant. First tent grow, different from a grow box. Got good neg pressure with excellent airflow....so all seems well. Put her on 12/12 today. new strain / new tent she is 23" tall now and she may fill that tent when she stretches. Will keep everyone up to date.