welcome . new grower here also. The T4 may be a little small for the 4x4. I have a T6 in my 4x4 and that seems to do the trick. you will be able to run it at a lower setting to pull the needed CFM and it will run quieter.
I run a T8 in my 4x8.
There is a wealth of information here so my best advice is to read, read, read., Read the guides. Read the Journals. There are so many good ones. this is a good one.
Good luck! don’t be afraid to ask questions. This isn’t those other places where people will call you stupid because you don’t know something.