Water bowl placement in a rack.

[loonunit]

No matter where you put the bowl, if it isn't attached, your BP will rearrange it around the tub constantly.

Seriously.

I do try to keep it away from the warm end, because that encourages bacteria growth. And I've come back a weekend trip and found the bowls completely evaporated down to hard water crystals from sitting directly over the heat tape. If I want to boost humidity, I splash some water around the tub.