Just to warn you that anubias of any species should not be planted in the substrate. The thick stem like thing that the leaves grow from is a rhizome, and this must not be buried or it will rot. The hair like roots are OK buried but not the rhizome. The usual way to grow anubias is with the rhizome attached to a piece of decor. It can be glued on or tied on with thread until the roots cling to the decor to hold it in place.