first things first
like the other guys said
theres too jmuch stuff in the tank for a tank thats only 3 weeks old
you should hav let your tank run at least 3-4 weekswith just the LR and then tested it no matter what.
there will always be a cycle small or large especiallywhen you put LR in a tank unless you moved the water with it that theLRwas inbefore hand
next thing you need to tell us is what kind of filtration you are using because if you're not filtering with anything thats a bad thing as well
lol
slow and steady wins the race with this hobby
ive had my tank up for about 7 months and i still dont have corals in mine
and with the kids wanting to see fish in there you might just hve to disregard them if you wanto have a sucessful tank
with every fish quarantining them is the best idea to make sure the fish are ok.
let us know what kind of filter you have and what kind of basic setup you have, and the test results would be a big advantage to us helping you out
it takes alot of patience with this, i learned that the hard way!
Drew