I would say if the manufacturer's recommended maximum number of outlets are close to what you are utilizing, do not worry about bleed off.
x2!
If you're less than recommended, what I'd do is get all of the tank lines running with the valves fully open, then open another valve to bleed. When you open the bleeder, if you see the furious nature of the air driving the filters decrease, adjust the single bleeder so the tanks are bubbling steadily at perhaps 80-85% of their maximum ferocity. If the single bleeder had no impact on the system, open additional valves until there is a decrease in performance of the tank lines and adjust the last one opened so the tanks are bubbling nicely.
As you add more tanks/airlines, eventually you'll need to start decreasing the amount of air being bled as the system needs greater volume to drive the tanks.
To help eliminate the hiss of air being bled you can attach large air stones to the lines being bled and place them somewhere out of sight. This does create some back pressure, hence the noise reduction, so you might need an additional bleeder after adding air stones depending on the situation.
