Yes, SANDFISHES is a Scrabble word!

Letter values in Scrabble US: S 1, A 1, N 1, D 2, F 4, I 1, S 1, H 4, E 1, S 1.

Is it a valid word?

SANDFISHES is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

either of two small silvery scaleless fishes of the northern Pacific that burrow into sand
fish of sandy areas of western Pacific and Indian oceans having an angular snout for burrowing into sand

Also: beaked salmon, gonorhynchus gonorhynchus.