The Urban Oasis? Collapsible Water Storage Barrels are a great compact solution for water storage, as a reservoir for hydroponics or for rain water retention. These reservoirs are made from a heavy-duty 1000 denier tarpaulin PVC material and range in sizes of 25 gallons up to 291 gallons. These reservoirs come collapsed and packed in a box that is easy to handle. A great alternative to bulky hard-sided reservoirs, Urban Oasis? Collapsible Water Storage Barrels come equipped with all necessary fittings including removable strainer, 3/4 in overflow fitting, 3/4 in click fit male connector, and 3/4 in tap.