Safe in the water
[Eppsocre solar brick installed in a fountain in Japan – Type SB200F]
Solar bricks are always exposed to foul weather and humidity.
Most other maker’s solar bricks are not really qualified for dewfall phenomenon, no matter what they have waterproof certification. The dewfall phenomenon is a different issue and required highly experienced technology and knowhow to prevent.
Apart from the presented information from the manufacturer, most solar lights are very weak for dewfall and waterproof, hence, you need a careful selection for solar light.
Eppscore will show you a perfect waterproof performance.
*Leaving alone broken solar bricks due to Waterproof & Dewfall (Other maker)