Sous vide whole salmon at what temperature? If I'm doing salmon fillets then I'll normally do 50c for 25 minutes, but a whole salmon is a different kettle of fish. I've done sous vide whole salmon on several occasions and I do 55c for 3 hours which works fine but dries out the fish a little more than I'd like.

I'm not really comfortable cooking anything at a temperature lower than 55c for long periods of time but I'd like a less dry whole salmon.

Does anyone else have any views / science on this one? Could I get away with doing a whole salmon at a lower temperature?
Whole salmon simply isn't a great candidate for low temp cooking in a water bath.  While you can achieve excellent results with portioned salmon, cooked at 50C for well under an hour, this timing is impossible for a whole fish.  It would be necessary to cook much longer.  The problem is you would probably have to cook the whole fish for a couple of hours.  This causes the enzymes to break down the flesh and you get a mushy, unpleasant product.  Alternately, as you experienced, raising the temp to speed things up results in a dried out product.

I would choose a different cooking technique for the whole fish...or portion your salmon into steaks or fillets and look here: http://www.chefsteps.com/activities/sous-vide-salmon--2