How do you vent a perpetual grow?

Hello, Sorry if this is a little long. I’m still working on my first grow and just want to try to avoid problems being late in the flowering stage. I’m trying to set up a perpetual grow but I’m unsure how with my current equipment. I have four plants in one tent (two mature and two in early veg) and at this point I want to try to get them in their own tents as humidity levels are starting to get a little too high for my liking. Currently between 38%-45% and rising with spring time weather.
Anyways, I have two tents(one 2.5’x2.5’ and one 3.5’x3.5’) two carbon filters, two 4" inline fans and one 4" booster fan.
Originally I was thinking one inline fan and filter for the fresh air intake into both tents and the other fan and filter to pull the air out of both but since the tents are different sizes I assume the air flow would be different as well.
Then I was thinking the Booster fan and filter as the intake for the flower tent, one inline fan to exhaust the flower tent into the veg tent for higher temps and humidity levels, and then the last inline fan and filter to exhaust the veg tent. But again I’m unsure if this will work as the booster fan isn’t very strong, especially when attached to a carbon filter, I also don’t know how the plants would react to negative pressure in a grow environment.
Basically my main goals are “fresh” air being circulated into both tents vs the rooms unfiltered air and then a strong enough extraction for each to avoid smell mold and/or bud rot.
If anyone has any tips/pointers it would be greatly appreciated but if not I’m sure I can figure something out. I just like to ask people who know what they’re talking about, if I can.

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Autos do well with 12/12 if you ever have slack in your flower tent. And they seem to be much faster in media/soil rather than DWC. DWC/RDWC grows big plants. Given your 3.5x3.5 this would be totally inadequate since Ive had Plant @36” in diameter. Stick with soil/media.

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I have 2 tents sharing one vent system. Since September, I have pretty much done a perpetual grow. I use one exhaust fan and filter, and rely solely on passive intake. I use a humidifier, when necessary. I can also block the connecting ports, if needed for any reason (such as bloom on one side and seedlings on the other ), and then run one tent w/o a carbon filter and only a clip fan for exhaust.


Sounds similar to my setup :wink: except I have aircon at one end with a fan between tents and carbon filter at the end with extraction fan.

I’m now going to try running the extraction back to the start of first tent to run full circle

I do the same as BTB run two tents (3x3,4x8) off 1 6" vent. Growing 2 plants in the small tent till I cut the two down from flower tent, move the 2 plants from the grow tent and use the 3x3 to dry in. The two plants now in the 4x8 flower tent will grow 18/6 about 10 days to flip to flower making them fill a 4x4 space. On about the 5th week of flower I plant 2 more seeds. Seems to be working out well.



Found this thread for you :sunglasses::facepunch:t2:

Building perpetual garden stage 1 :arrow_left:


i’d try 4" inline/filter pushing air into the 3.5x3.5, the other inline/filter exhausting into the 2.5x2.5, and the booster fan exhausting the 2.5x2.5.

this would give u filtered air into both tents and if any smell gets out of the tents the intake fan/filter will get it.!