I agree with everyone else- waterfalls are a big no. They are hazardous in more ways than one. You should take it back to the store.
Also, I wouldn't trust liquid vitamins. It would be way too easy to overdose it. You should only really be using vitamins once a week for a young cham, and once a month or so for an adult. You should get a good calcium supplement without phosphorous and without D3, a calcium without phosphorous and WITH D3, and a good dry dust multivitamin (herptivite by RepCal is good, as is VitAll by MinerAll)
Your misting system should be on a timer. Have it go off at least three times a day for about five minutes.