the sandfish inhabits shallow tropical waters, <20 m deep. they prefer seagrass meadows and muddy bottomed substrata with high nutrient levels due to their diet preference. they do have a tolerance for lowered salinity, down to 20 ppt, such as that found in brackish water. sandfish play a key role in the health of their habitat; like most sea cucumbers "h. scabra" are bioturbators and play a key role in reworking the sediment and ensuring that organic matter is evenly distributed for the ecosystem to function, and have a subsequent diet of detritus and other microorganisms.