[Gecko] calcium / vitamins

[Jason LaFountain]

Ok i've read that geckos need lots of calcium, and vitamins to be healthy, so far i've gathered that I should,   1) keep a calcium dish in the tank at all times 2) dust crickets w/ calcium every feeding (for jouviniles) 3) dust food w/ vitamins every other day? I have also heard about d3, and that too much is bad so you should get two kinda of calcium one w/ d3 and one w/out. However, i have seen most vitamin supplements already have calcium in them, so do i still need to dust w/ calcium if that is so?   Thanks for any help, Jason