so petco is having their $1/gallon sale and i am going to go grab a 20 long tonite for my 3 american toads...this is being done without spouse approval, teehee, so i may not get it set up right away, BUT i figure i will at least get a start on a new home for them. what type of lid would be best for this type of set up, just a screen with a light on top??

Right now with just a 10 gallon, it isn't that difficult (or too expensive) to just dump out the used substrate (eco-earth) and refill with new stuff every 3-4 weeks. My question(s) are more or less in regards to the cleaning of the new tank. generally speaking, how often should substrate be changed out? i try and pick out any poo i can visibly see of course, and water is changed daily.... humidity and temps have been around 70, give or take a few degrees. i do plan on adding a drainage layer of gravel to the bottom as well, and will have a UTH on the bottom left side of the tank.

ANY and ALL advice is welcome for my set up!! thanks in advance