Blueberry Poison Pie

Yes it can be a problem. You want negative pressure to make sure that all air gets pushed out after it has gone thru your carbon filter. positive pressure will push out air where ever it has lowest resistance. eg cable holes, opening of the door etc etc. Also, not as important if you have a premium tent.. negative pressure also helps with giving the tentpoles a uniform pressure , the tent becomes more stable and it also keeps poles staying attached to one another