I once read in a german magazine of washing techniques of film..

and the one I use, and teach my students is simple and quick:

use 20-21 degrees C water.
fill the tank with this water and agitate "violently" (kipping) 5 times - change the water and agitate 10 times - change and agitate 20 times...
that's it.

apparently the chemistry/water interchanging is best at 20-21 degrees, so it won't help to raise the temperature..
(or lower it)

this is the "washing maschine" principle. it is rather quick - it saves a LOT of water and it works (for me..)