Swimming Pools / Containment Vessels
1: Using a dark food coloring, release along the length of the suspected crack. You will then be able to see exactly where and at what rate water is leaving through the crack.
2: Using HyperFlex, slowly release over the areas that are drawing water. The HyperFlex will be pulled by the water through the entire crack system. This will work for wall cracks if they are drawing water.
This technique is for slow weeping cracks as it would be necessary to drain the water for a large high flow leak.