Evacuated from NO, LA ~ need some DBT help

Hello All, We left Slidell, LA on Sunday due to approaching Hurricane Katrina. At home in Slidell I always had the luxury of “fresh”, brackish bayou water for my young DBT “Flipper”. Now we are on the road. And, since conditions in the car were cramped (to say the least) I put Flipper in a large plastic tupperware bowl with holes punch through the top for fresh air with about 3 inches of bayou water in the bowl. Not the best DBT habitat I’m sure, but it was what I came up with in a pinch. Needless to say, after just a couple days his water needs to be changed. What do I do now? We are in a Motel 8 in Memphis TN. I have access to bottled water and distilled water. Should I add some salt to one of these types of water? Note: We will be evacuated AT LEAST a week. As always, your suggestions are greatly appreciated. Thanks so much, Renee’ 🙂