"I would really love to see optional ports added to the fusion reactor where you can specify access to each internal tank. Trying to automate an extended chain of reactions is very difficult as you can not specify what input tank to pump in to and what output tanks to extract from. It would be nice if there was say, four ports on the top and bottom of the reactor that could be changed via a gui or right clicking with a wrench in world that changed what tank they accessed." - ElectroFried on Reddit

Put on hold for now, as fitering is made a lot easier with the addition of fluid container interactions with the machine's blocks - now fluid can be taken out of machines and used to set up filtering before any piping is done.