The excel is a source of added carbon, replacing CO2. Most of your plants are going to absorb through their roots in the substrate so that's why the root tabs are your best bet. You could also add a liquid fert like Seachem Flourish to the water column and the anubia and javafern will take advantage of it.
All except the anubia and java fern just get planted right in the substrate. Just dig a little hole, spread the roots out, cover over them iwth substrate. Make sure you don't go above the crown though (where the leaves start). The anubias and javafern can grow two ways. You can either tie them to wood or porous rock, OR jsut lay them ON the substrate, lightly cover the smaller hair roots but leave the rhizome above the surface, and they'll grow into the substrate as they see fit. this doesn't harm them at all, I've grown very healthy anubias and java fern this way and they will eventually root in the substrate without ill effects.
All except the anubia and java fern just get planted right in the substrate. Just dig a little hole, spread the roots out, cover over them iwth substrate. Make sure you don't go above the crown though (where the leaves start). The anubias and javafern can grow two ways. You can either tie them to wood or porous rock, OR jsut lay them ON the substrate, lightly cover the smaller hair roots but leave the rhizome above the surface, and they'll grow into the substrate as they see fit. this doesn't harm them at all, I've grown very healthy anubias and java fern this way and they will eventually root in the substrate without ill effects.