I've done this before and has helped with some zoas staying closed all the time or being partially opened. The dip has also killed some of my colonies so use at your own risk.
1 furan 2 packet per 1qt fresh saltwater, same paramaeters as tank water i.e. temp, salinity etc..
I use a small heater and micro tunze pump for flow, they say the higher the temperature the better the furan 2 dip works so maybe go to ~81°
Dip the affected corals in furan 2 for about 5-15min
Then dip in a seperate container that has tank water to rinse of the furan2 then place back into tank, recomend starting with low flow and low light area until coral gets healthier.
I'm not home to verify the actual amount per packet but based on my math I think you'll need 2.6grams or 1tsp per packet.
The jar of Furan 2 covers 850grams/3270gallons = .26grams/gallon
The packet of Furan 2 covers Xgrams/10gallons
So the packet has 2.6grams/10gallons
Converting from grams to tsp I estimated that Furan 2 has a consistancy of flour, in using an online conversion tool 2.6grams of all purpose flour = 1tsp of total volume.
Good luck.