yea or since it was just the weekend maybe they are all backed up and seed companies sort of slack a bit anyway...did you try their customer support telephone number if they have one? if nothing else i would just call my CC company and dispute.
you can use either, preferable over soil get some Jiffy peat moss and expand those and use them, also you can find under the DIY section a way to make a cheal DWC cloner from Walmart
it will max out when it goes into flowering, a good 5 foot plant may have a root ball the size of a bowling ball and the roots extend to the width of the plant
yea and if their are just sprouts it should out grow the abnormality...also what kine water are you using? the white residue may be from salt or chlorine
400 watts if definentally enough for your 6 plants just keep the light 18-24 inches above the plants, tossing in some CFLs would just raise you electricity bill and temp in the room.
nah a 250 covers 3 squar feet 400 covers 4, 600 covers 4, and 1000 covers 6 square feet, i would like to know were you got your info from? I got mine from http://www.intl-light.com/handbook.html