Nope. Using a hermit crab isnt going to cycle your tank, unless you mean an actual piece of crab meat. lol You need to supply an ammonia source and watch the ammonia rise, then the nitrites and then the nitrates. After that is all said and done you should have 0 ammonia, 0 nitrite and high nitrates. You then do a water change to get the nitrates down and THEN you can add fish slowly.
It usually takes anywhere from a couple weeks to a month pr two to cycle a tank. Unless you use all live rock in which case your cycle could be alot shorter.