Fermaid O is pricey. Are you sure you need 43 g though?
Got me Pete if its right or not.
42.3gr according of fermaid O (TONSA) and this calculator:
http://www.meadmakr.com/batch-buildr/heres what it says on the calc: "The total amount of Fermaid O that will be added to your must is 42.3g. The nutrients will be divided into 4 staggered nutrient additions. To avoid mead eruption accidents, degas must and dissolve yeast nutrient doses in 1 cup must prior to adding to the fermenter.
At 24, 48, and 72 hours after you pitch your yeast, add 10.6g of Fermaid O to your must.
When the must reaches the 1/3 sugar break (1/3 of all available sugars are consumed, i.e. 1.120 starting gravity reaches 1.080 or 21 Brix reaches 14 Brix), but no later than 7 days after yeast pitch, add the last dose of 10.5g of Fermaid O. "