It'll take a minute or two for the tube-style thermometers to register the water temp... it's best to ensure the temps match within a degree or two (especially when you are heating the tank)... b/c there would be a significant difference between room temp water and heated tank water... and fluctuations of greater than a degree or two can stress them, opening them up to illness.

I'm glad that the tanks haven't been washed with soap. Dawn, from what I understand, is the mildest of all the dishsoaps (and is often used on birds caught in oil slicks I believe).... but I personally wouldn't use them. The dollar stores are great resources for a lot of fish tools... turkey basters, measuring cups, little plastic containers to presoak food in... just rinse them well in hot water initially and dry them with paper towels. I've even found critter keepers at my dollar store that I use for temporary holding/floating tanks... you may be lucky to find similar things at yours.

If you can conveniently do 3 feedings per day... that would probably be easier on her given her fragile state.

Michele