There are so many stores that say get a damsel they are hardy and put it in there. Yes they are hardy little guys but cycling will kill them or cut their life short. Most people start out with damsels loving them and then end up hating them.
The only way you won't be going through a cycle now is if all your live sand and rock came directly out of a well established tank. I have upgraded my tanks and have always been lucky enough to get the sand from someone taking a tank down. The first week there is an ammonia spike and then it drops back down. It is called a soft cycle.
One thing I have learned is to drip acclimate fish and test the store water against mine for anything else. If the water is .001 difference I will drip acclimate things like crabs and shrimp.