i dont use their mix either, i have 2 set up and working a treat
fill till the botton mark ( inside) with normal white sugar
fill to the second mark with tepid( just warm) water
add half a t-spoon of fast acting yeast ( tecos do one in a green box-its satchets)
stirr it
place the ladder in a bucket fixed to the sides, so if it goes wrong (ie,leaks) it wont leak into your tank) if it does leak, pour a small amount of the mix out and try again if no leaks add it to your tank, and your away !!
good luck shelagh xxxx