I have 200lbs of sand i need to add to a 300gal established system. How many pounds do u think i can safely add before it starts to effect the system. I have 400lbs of live rock and all my corals and few fish. There is currently no sand in system at all. I was thinking of adding 100lbs or may add it all since it is live sand and is new in the bag its not reused sand. what do u all think?