The best place to get 'real' acicularis is at Lowes (havn't tried Home Depot). Unfortunately, they only sell it during warmer months when they offer their pond plants. It's labeled as needle spike rush. It is definitely much taller that the potted plants sold in fish stores. Eleocharis vivipara is the tallest hairgrass i've seen (also as seen in many of Amano's tanks as a background plant). I agree that many times the eleocharis acicularis sold in fish stores is really eleocharis parvula.