You can also put the rat inside a ziplock sandwich bag with the air pressed out, then put the sandwich bag into the water to thaw. The rodent stays dry and does not collect as much substrate while the snake drags it around. There is also less chance of the water washing away some of the rat's natural smell which the snake also uses in addition to the warmth and lastly sight. I followed a video I saw on youtube putting them in ziplock bags then having the bag between 2 tubs. the first tub is filled half full with water then the bag with rodent on top of this water, placing the second tub on top of the bag and filling with water. This way the rodent is sandwiched between 2 tubs of warm water and doesn't get wet. I just use 1 bag per feeding day then trash them. fairly in-expensive.