An apparatus , comprising: a load cell ; a storage tank ; a first plate removably attached to the storage tank; one or more compression springs disposed below and supporting the first plate ; and a platform comprising: a second plate , wherein the second plate is disposed between the first plate and the storage tank , and one or more fasteners that extend downwardly from the second plate to engage and exert a force onto the load cell ; and one or more legs , wherein each leg corresponds to one of the one or more compressions springs, wherein each leg extends from the second plate through a through-hole in the first plate and through a center of the corresponding compression spring, and each corresponding compression spring is supported by a foot (116/118, 216/218, 266/268, 296/297) positioned on the corresponding leg of the platform; wherein each leg of the one or more legs and corresponding foot are attached to the second plate; wherein a weight of the storage tank and its contents exert a force on the first plate which in turn compresses the corresponding compression spring positioned about each of the one or more legs, wherein the corresponding compression springs exert a force against the feet of the one or more legs thereby exerting a downward force towards the second plate through the legs. a load cell ; a storage tank ; a first plate removably attached to the storage tank; one or more compression springs disposed below and supporting the first plate ; and a platform comprising: a second plate , wherein the second plate is disposed between the first plate and the storage tank , and one or more fasteners that extend downwardly from the second plate to engage and exert a force onto the load cell ; and one or more legs , wherein each leg corresponds to one of the one or more compressions springs, wherein each leg extends from the second plate through a through-hole in the first plate and through a center of the corresponding compression spring, and each corresponding compression spring is supported by a foot (116/118, 216/218, 266/268, 296/297) positioned on the corresponding leg of the platform; a second plate , wherein the second plate is disposed between the first plate and the storage tank , and one or more fasteners that extend downwardly from the second plate to engage and exert a force onto the load cell ; and one or more legs , wherein each leg corresponds to one of the one or more compressions springs, wherein each leg extends from the second plate through a through-hole in the first plate and through a center of the corresponding compression spring, and each corresponding compression spring is supported by a foot (116/118, 216/218, 266/268, 296/297) positioned on the corresponding leg of the platform; wherein each leg of the one or more legs and corresponding foot are attached to the second plate; wherein a weight of the storage tank and its contents exert a force on the first plate which in turn compresses the corresponding compression spring positioned about each of the one or more legs, wherein the corresponding compression springs exert a force against the feet of the one or more legs thereby exerting a downward force towards the second plate through the legs. <EOS>