Hello
You can just wash it out with dilute vinegar water just as you would with a new tank. You might want to fill with water and see is it leaks before stting up for fish.
gary

You may also want to use a strong bleach solution, at least 1 part bleach to 19 parts water. Get a powerhead or pump to move the water around for a day or 2. Snakes and the rodents they eat can foul the tank pretty good from urine. Just a precaution, may not be necessary. This would also help tell you if the seams are still in tact and can hold water. After the bleach, rinse it well and sun dry it for a few days.

Thank you both for the info. Afetr Mirakaih (the snake) passed away, we dumped the bedding out and rinsed the tank and filled it with water to see if it leaked... There were no leaks noticed, but I knew there had to be more to clean it. I will do the bleach or vinager (I am sure I have one of the 2 here at the house) Thanks so much again

Heather