hey people..
ive recently found my plants are lacking magnesium and are showing some stress on the lower leaves.
done a little bit searching and found the quickest and easyest way to resolve this is epsom salts, i have got my hands on a 1kg bag of this stuff however im a little unsure how much i need.

my system is flood and drain with the seperate brain pot, i was thinking of dropping some epsom salt into the brain pot and flood the system to give the plants a quick boost

my pots are 10ltr, brain pot is 20ltr and resivour is 100ltr - can you guys give me a rough guide as to how much i should drop in and if i should drop it in the res?

cheers people
ken