lights initially very bright but not for long

The glow sticks are the enabled very bright, but after an hour, the brightness after.
One of four glowstick was slightly leaking when it is held in the warm hand, forces the liquid to the outside.
The Starlights See similar to the figure of (not rounded ends) and have on one side a plug welded probably should be. In the interior two half as long glass bulbs are not break too easily. This can be determined also activate in two steps in order to extend the burn time.
For the leak and the rapidly diminishing brightness's of me ever a star deduction.