After thinking about this, I think a golem core would be the best way to do this. You would setup the water pool, with or without accelerators, place the golem in the pool of water, then cap it off with a ME interface. The golem would grab seeds from the interface, place them in his pool, wait for growth, deposit them in the interface, and start the whole process over again.
The golems presence in the water pool may even give a slight growth acceleration.

I would call the core something like "Crystal" or "Quartz"