Why do my dwarf angel fish keep dying

[leo12345]

Today my coral beauty died super unexpectedly because he was extremely healthy looking, i had a flame angel too that also died unexpectedly after being healthy what am I doing wrong, They only thing i did before it died was i put some rodi water in the tank to top it off because of evaporation but i have inverts and there more susceptible to dying from sanity changes and they were fine but could this have killed it? I also heard that they catch fish with cyanide and they die unexpectedly, could this be the case?

 

[vetteguy53081]

Flakes and pellets are fine - just not as a primary diet. I use flakes and Pellets in my auto-feeder daily for 37 fish which include 21 large Tangs as they are literally fresh food that is freeze dried .
Some of the best pellets are new era and TDO which come in many pallatable sizes.
To get off food discussion, at my LFS, the coral beauties seems to be weaker from transport compared to other dwarfs and required longer acclimation.
PLOP and DROP after salinity match is NOT recommended as you want to in addition to salinity to Ph. Fish in bags produce carbon dioxide and ammonia. The carbon dioxide lowers the pH of the water in the bag, That in turn makes the ammonia non-toxic to the fish. When you acclimate them, if not done just right, you drive off the carbon dioxide faster than you are diluting the ammonia. That raises the pH of the water in the bag which is why you never want to use the water from the bag