Thought I'd start by scribbling down the Agar recipe:
Add 7g agar flakes to 1.75l water in 2l beaker.
Place on 1000W burner of 2-burner hotplate.
Rig up a shroud and lid around beaker to reduce heat loss. I borrowed a chunk of pipe and PVC from the shop this time (see photo). The spot I used in the cage had a draft, so I used the blue foam to block it.
It took about 20min on high to get to a boil. I stir every couple of minutes using a glass rod Chris found to the left of the cal lab sink.
Reduce heat to medium-high and simmer with lid off (packet instructions said for 5min, TP01 said 20min, I did 15min this time).
Let cool until milky white (several hours).