Water crystals are a primary source of water for Dubia Roaches. They will help keep the feeders properly hydrated as well as keep a constant humidity in the enclosure. These water absorbing polymer crystals can absorb up to 400 times their own weight in water. Use 1oz of water crystals (by weight) for every gallon of water. Smaller quantities use 1 teaspoon of water crystals for every 8oz of water. Allow the mixture to sit for at least an hour, strain out the excess water and then place the water gel in the enclosure.
I got introduced to water crystals when I started working at a local pet store and found that they are the best things ever! When I bought my first batch of roaches, I just had to get these too! Love the crystals because they last forever and you don't need much to fill a dish and make the roaches happy!