The minimal amounts of water needed to assure complete suspension of 50 g of 4 different antidotal charcoals were determined. The water volumes ranged from 170-192 ml. The total suspension volumes (water + charcoal) ranged from 201-221 ml. Since manufacturers package 50 g charcoal formulations with a total volume of 8 fluid ounces (237 ml) there is only 16-36 ml of water beyond the minimal amounts needed for suspension. It is recommended that water in an amount of 10% or more of the total volume (ie 24 ml or more) be added by manufacturers to help prevent compaction during storage, or be added by users to aid in resuspension and to increase the suspension flow rate during delivery through tubes.