An apparatus (100,200,290,291), comprising: a load cell; a storage tank; a first plate (120, 220, 270, 293) removably attached to the storage tank; one or more compression springs (130, 230, 280,295) 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 (114, 214, 264, 292), 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 (120, 220, 270, 293) removably attached to the storage tank; one or more compression springs (130, 230, 280,295) 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 (114, 214, 264, 292), 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 (114, 214, 264, 292), 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.