<p>A fluid flow indicator for observation of low flow rates in liquids includes a capillary tube (12) slidably mounted at each end in passageways (4) and (5) and biased into a no- flow indicating position by a castellated elastomeric membrane (14) providing a sealed barrier within a chamber (1) between a first zone (17) and a second zone (18). Fluid flow introduced through spigot (9) causes the capillary tube (12) to slide to the opposite end of the passageways (4) and (5) whereupon the deformed position of the elastomeric membrane (14) can readily be observed through transparent walls (3) in the chamber (1). Upon cessation of flow, the elastomeric membrane (14) causes the capillary tube (12) to revert to its original position.</p>