Aquascapes in the Aiea Town Square might have dwarf hairgrass. Prolly the best fish/plant shop on Oahu I have ever visited.
EPC #329 - VPC #59
20L - P. axelrodi, C. macracanthus, H. ocellifer, T. albonubes "gold", Stiphodon sp. gobies, Sailfin mollies
16BF - T. albonubes "gold", A. dolichopterus, Ps. gertrudae "Aru II"