Well, I bought it off Aquagreen, who I believe buys from Simplegrow. I have asked the same question on
www.aquariumlife.com.au, Aquagreen is a sponsor there.
If you havent signed up I would highly recommend it, probably the most active Australian planted tank forum I am a member of, and a great place to trade plants. The sponsers are fantastic too (if you are ever placing an order let me know, we can share postage!).
I havent got an actual answer as yet, though a lot of posts because I left a decimal place out on my dose amounts.
My username is same as here. Make a post there and lets see if we can get it resolved.