Thank you all so far, interesting perspectives and experiences.
These are Dwarf Blue Crayfish only get up to 2.5" And more close to mouth size for a large Clown Loach. I think the Dwarf crays would die before the Clown loaches got big enough to eat them.
While calling around to lfs
for Clown Loaches I was told there was a pair they just got in which were over a foot long for $110 - not in my budget but reminds me of what size they can get!
Some one here had a tank of them too and lived nearby so I got to see them play and it was a really fun thing to watch them all together!