Ammonia elevated >0.02ppm un-ionised
The un-ionised ammonia causes toxicity. Calculate this from Total Ammonia with RSFP Ammonia Test and chart therein.
Any abnormal parameter of Environment, will cause a few or many of these symptoms. Check ALL water parameters, as well as water supply.
Usually can be traced to some abnormal variant in water, or other parameter, e.g. Oxygen level, Temperature changes, Ammonia or Nitrite, pH change etc.etc. If cause is found then outlook is good when abnormality is corrected.