Rainbow boas are not as difficult to care for as many believe. 1. Use cypress mulch. it doesn't mold or rot and is non toxic. Doesnt smell bad easily either. 2. Block off 80-95% of the top of your tank, depending on the size/shape of your tank, age of your snake, and size of your water dish. 3. For snakes under 1 year, overall tank humidity is critical and I recommend a tupperwear humid box. The snake isn't totally stupid, it will seek out the most humid spot as long as that spot is also a reasonable temperature. Mine escaped once and I found it in the laundry machine. 4. After 1 year, the snake will start to get more of its hydration from drinking. Humidity becomes substantially less important after 1-2 years as long as the water supply is large enough and maintained regularly enough to allow the snake to soak. It will soak, it has instincts. GOOGLE PORTABLE HUMIDIFIER!! they are made for countertops or small rooms. You simply screw a water bottle in to the small stand, plug it in, and boom! 6-12 hours of a nice steady foggy mist depending on size of bottle. a 32 oz water bottle could last for probably 25-30 hours! This will really help with an enclosed lid!!! they're only 25-60 bucks. Don't let the humidity factor drag you down. The main issue is keeping the water dish clean and dealing with the annual winter hunger strike and having to throw 10 dollar rats away per failed feeding. Your snake WILL have major problems shedding if you don't keep the tank humid though at any age AND also don't have a water area plenty large enough and clean enough for it to soak in. A full grown adult should be in a 90 gallon tank minimum. silicone some glass in on 1 side have a water pool area. Make it about 10-15 litres of water. get submersible filter rated for 20 gallons and rinse the filter out and replace the water whenever it starts to look unclean and spot clean the water for poo regularly. Trust me it works. Have the tank on a slight slant so that the water collects along the corner and is easy to siphon out, or silicone a slanted glass floor into the water area if you have the desire. Use high grade non toxic silicone itll be like 20 bucks for a tube. The water pool and movement create so much humidity that you'll find its easy to cover too much of the lid.