Fan Question

Hello all.
I've gone slightly overboard with the size of extraction and inlet fans and want to put a speed controller on them.
As the inlet is 125mm and the extractor is 100mm, could i control both with the same controller? My thought is
that more air would be entering than leaving regardless of speed, as long as both fans are running at the same
speed due to the inlet being larger than the outlet.

your extractor would have to move faster as it has to keep up with the larger fan bringing in more air. this isnt a problem unless you have a 100% air tight room.

would it make life easier all round if both fans were the same size?

Just run the exhaust and have a passive intake, I just use the pushpin timer and run it 15 on 15 off 24/7 for fresh CO2 enriched air. Keep the fan for a spare or for the cooltube you should be buying next.

Cheers.......thanks for the help!