I use Equine Fresh all the time...for my rats.

In its pellet format it would work fine - with no issues (I have used it for my corn snakes for over a year)

But...when it breaks down (like in major water spills and such) it quickly turns into saw dust. Wet it sticks to everything and dry is dusty...so I would NOT recommend it in a snake cage where lots of water get spilled (like in your case). As this dust (wet or dry) will get in your snakes heat pits and they will breath it in.

Hope this helps.