If you don't have anything fish or anything else in the tank then I would just leave the water alone and not do any water changes. Some people will add a cheep, hardy, small fish to the tank to cycle it. Some add something like a dinner shrimp and let it decompose in the tank to help the cycle along. Some add just pure ammonia to the water to get the cycle started. Everyone has a favorite method.
Mine would be to get the water and tank full and make sure your salinity ect. are all about where they should be, wait about a week and to add the LR. I then added the cleanup crew slowly starting with snails. My tank never did a typical cycle though the LR and all the bacteria that was on it already with the very slow addition of bioload, made it impossible to read anything on my tests for ammo, nitrite and nitrate. I hope this helps.
Oh I did not do a water change for 2 months after filling the tank.
