[Bert H]

Lose the crushed coral!!! I hear you that $$ is an object, heck I'd prefer to go to a local stream or river and dig up a couple of tupperware containers of gravel or sand than use crushed coral. The diy CO2 you're using on this system will make very little difference when it's battling the very high hardness levels due to the crushed coral. My 2 cents.

 

[Bert H]

Yes, those are all plants which will do well in hard waters. But keep in mind, some of those do have decent lighting needs, and if you're going to keep cichlids with them, you'll have a tough time keeping them where you put them.

As Texgal says, changing out a substrate doesn't have to be that difficult, especially in smaller tanks. I once ripped out an entire ugf and substrate on a 29 gal, while keeping all the guppies in the tank. It took me a whole day, but I didn't lose a single one.