Please help fish deaths and Im puzzled

[markc]

I have lost a number of fish which have been added over the last month.
All water indicators are good ph 8 to 8.3
Amm.o nitrate 5 phosphate 0 salinity .o23 ect
Each fish two tangs and a coral beauty have gone the same way
rapid gill movement , near to the surface ,dead in 24 hrs.
At first I put it down to Iodine od.tests did show this to be the case .
Another fish added same thing, this time Ithought it may be due to too rapid a rate of Kalwasser additive.
Coral b added same result Iam now looking for some kind of pathogene Gill flukes? Ithink that I have experienced multiple problems what do you US guys think? ALL OTHER FISH ARE FINE damsals ,chromes blennies clowns hum bugs no problems since Iodine problem identified.
ps Our thoughts are with the 7

 

[reefNewbie]

I would get a test kit for the amount of oxygen in the water. I forgot what its called now, someone help me out here.

 

[marty55904]

How long you had them? mabye bad from purchase?


ps. thank you

 

[markc]

Ill get the test kit but if the results are low how do I improve this?
Ithink that the tank has a lot of surface movement and I run an air stone in the sump 24-7

 

[aquarist=broke]

how are you introducing these new fish?(acclimation process)

 

[markc]

By the book. 3 years of keeping a reef tank I have lost more fish in the last 2 months than in this period.
PS the corals look great!