Hi all. I've set up a small aquarium for my son of 8. We have only gravel in it and after letting it cycle for around two weeks I got him some micro swords that are going well. He seen some dwarf hairgrass the other day and wanted it as well so I got some of that as well. The hairgrass has been in the tank for about 3 weeks now and there's no sign of growth. Should I be adding some root tabs or fertilizers? There are no fish in the tank yet but might add some collie loach's and a bristle nosed catfish