Bought some Avicularia purpureas.

[Storm76]

There isn't a drowning risk...even adult Avics can "walk on water" without breaking the surface tension:

http://www.masterfile.com/stock-pho...on-River-caused-by-runoff-from-the-Andes-Peru

http://www.masterfile.com/stock-pho...(Avicularia-sp)-floating-on-Yarapa-River-Peru

Slings have a wax-layer that develops I believe from 2nd instar on and I love those videos - thanks for posting them again to dismiss this myth, mate!