I don't
bathe my dragons really unless they are dirty.
Clogged femoral pores aren't something you'll normally need to worry about. Especially if they have items in their tank like rocks/logs etc.
20-30 minute bathes is probably stretching it. But some dragons enjoy the water and might enjoy being in their that long. When I
bathe it's typically 5 minutes or less.
I don't measure the water temp, I just feel it like you would for a baby human.
-Brandon