its just depends on how many fish you are trying to add. With a 100g of water and 50lbs of lr you should be able to house a few fish until the rest is seeded, especially if you have live sand. i would wait until the whole thing is seeded and stable before adding your whole wish list for the sake of less flucuation and water changes. As the seeding progresses, which might take a month or longer, your not going to get any spikes because of the gradual progression. My advice is treat the tank is if it only has 50lbs of lr and add fish accordingly. Then after awhile add as if you had 100lbs of lr. Plus as you already know you should not add all fish at once and should spread it out over several weeks. This will give you ample time to QT your fish anyway.