i'll assume your are in the UK, as the figures are for a Redclaw. 25ukg minimum, but i would reccomend 40 for a full grown Cray, and they can grow from 2 inches to over 6 in less than 12 months. As long as you secure the lid depth is not too much of a problem, though if the water is more than 16 inches i would advise some sort of platform for the cray to climb, they love base jumping. though they dig and dig, even getting down to the glass. i have still never heard of a Cray damaging a seal. lighting and filter are as for fish.
or i suppose you could put it in a small tank! but an 8 inch Redclaw with 3 inches of claw and 8 or more inches of antenna makes a 4 foot tank look small, when going for a walk. thats 11 inch plus of Cray, would anyone suggest putting a 11 inch fish in a 20usg tank? perhaps!