The rock will give you a certain amount of die off but at a week you really shouldn't be considering animal additions just yet. The tank will be another few weeks at least before it's ready. To be honest, I'm suprised the hermits are still alive 8O . Most inverts cannot tolerate NH3
for any length of time.
As far as the anemone is concerned the tank should really be run for a least a year before one should be purchased. The tank will not really be stable for the 8 months at least and needs the time to mature properly. Anemones need pristine conditions that a new tank cannot provide. If a hosting anemone, you will also need to consider good lights. Your profile does not indicate what you have for light so I can't comment as yet.
The fish should not be added until the NH3
have reached zero and stayed there a while. What I would suggest is setting up a smaller Q-tank
so that once the NO2
does start to fall you can purchase the clowns and place them there. After their 4 week stint in the QT is over, the tank should be somewhat ready as well providing the fish remained healthy.
Keep in mind though that if you do decide to add more rock it should be done as soon as possible or cure the LR
seperately after the fact. Dead base rock will not need to be pre-cured.