I concur with the water crystals. I have found many people post that they are not necessary if you feed lots of fruits and veggies. Yeah they have moisture but i don't believe it is enough alone to provide moisture throughout your bin. I have a large amount of breeders that will specifically give birth in or very near the crystal dish which makes it evident sufficient moisture is important to reproduction. Of course it is impossible to drown in water crystals i might add.