Just started growing second week in veg

If I have the air getting sucked out of the tent from the fan is that ok if I don’t have air getting sucked in with another duct fan ?!

A tent under negative pressure is OK as long as you still have plenty of air intake. If the exhaust fan is working too hard because of a lack of intake/ vents it'll wear out faster, and potentially have a higher fire risk.

If I don’t have air sucking out of tent or blowing in is that fine @Johiem

As long as you have the passive intakes at the bottom of the tent open, you'll be fine..

Antc420 said:

If I don’t have air sucking out of tent or blowing in is that fine @Johiem

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I would still have some sort of air exchange going on. If the tent is closed up and only circulating the air contained within it'll will, eventually, deplete the CO² and slow, if not stop, photosynthesis. So, yes, air exchange of some sort. Be it passive with the vents or an unzipped bottom of the door, or assisted intake, you need one or the other for healthy plants. Do you Need an intake fan? In A tent 5x5 and under i can't see the benefit. A properly sized exhaust fan will provide plenty of fresh air to your plants

I have a 6inch exhaust and a 4inch exhaust I tried to just bring in fresh air but my humidifier was staying on all the time not sure what to do @Johiem

Where is your humidifier situated? In the tent? In the lung room? Unless the air you're brining into the room is as humid as your humidifier is trying to make it, it will always be on. I am constantly exchanging air as such I'm at the mercy of the weather for humidity control. Between the hard water stains on my plants and it never shutting off, I got rid of my humidifier, and I just foliar spray when it's too dry.