Dr Ph Martin’s bleed proof white is a must have for serious stamp artists! However, it needs to be kept sealed tightly, and stirred each time you open it. (wooden coffee stirrers work well). Try to wipe the threads and the top of the jar off each time you use them to make it as air tight as possible. Having said all of this, over time your fluid will begin to thicken and dry out. This plastic dropper is the perfect accessory! It is will not break like glass droppers, and will allow you to add water to rehydrate you bleed proof white one drop at a time. It is large enough to not get lost (roughly 6″ long). We highly recommend these!