Tub question

[Sharlynn93]

ok, I have never used a tub for a snake, so need some advice....I am POSSIBLY getting my husband a baby brazilian rainbow that he has been oogling over for the last month for christmas...right now she is at a pet store in a 20 long with a screen lid with a heat lamp so i KNOW she isn't getting the right humidity and temps, so I think a tub would be best for her...what I have "on hand" is a 58qt sterilite tub (no locking hinges on the lid) what would I need to do to it to make it a temporary habitat? or should I get one that has the locking hinges? is it ok to use a heat mat? (would have to order a thermostat online which would take a week but would a smaller heat mat for now be ok? looking to possibly get the snake tomorrow or the next day to make sure it doesn't get sold before I can get it for him...) figured possibly making a thick layer of substrate to knock down the surface heat? would that work as a very temporary solution?