On Tuesday, May 16, 2017 at 3:46:47 AM UTC-4, Aussie wrote:
I'm playing around potting some electronics for immersion in water up to
10 metres.


Any suggestions?


A good many years ago I was involved in something similar. Instead of dealing with water it was dealing with high voltages and vacuum. The first try was epoxy potting. It cracked in temperature cycling.

So somewhat flexible polyurethane potting was tried. It did not adhere well enough.

The solution was a metal box with a gasketed lid. It was great for reworking as in did not have any conformal coating to remove. The connectors did have to be a special design. They were kind of like morse tapers. Necessary because the voltage was about 2000 volts. Surprise , surprise the connector was designed on paper and worked without having to be revised.

Dan