George et al, this is easy as pie.

You have a dense rug, established root systems, zero algae, well cycled N cycle in the sediment(bio already there after 3 weeks).

Add water, CO2, filter and ferts.

People always carry on about how hard it is to start up HC or a new tank.
Well, here's a very simple solution, better and simpler than anyone else's I've ever read.

If you have a simpler easier fool proof no algae and dense rug method, let us know

Why limit/torture ourselves with water if it's not even needed in the start?
Many do and assume they must, but that is their own limitation that they place on themselves.

Be careful about doing that type of behavior in this hobby as well as life.

Regards,
Tom Barr