Last Saturday I spent several hours jacking my boat to get it dead level for applying a new boot top . I used a water level for this operation. It was simply clear 1/2 inch garden hose. It was only coming towards the end of the task that I realised -water does not find it's own level!!! It appears that small air bubbles got trapped along the hose leading to marginally different weights in each of the hose legs. Has anybody had a similar experience and solved the problem?- perhaps using an additive to reduce surface tension and hence loosen the trapped bubbles?