About: http://webisa.webdatacommons.org/3345644

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	If cost is an issue, and I can appreciate that issue from my experience too, there is also bulk gravel at aquarium stores or landscape/stone quarry places.
http://www.w3.org/ns/prov#wasQuotedFrom	tropicalfishkeeping.com