If your turtle was sick, here would be some of the indicators, soft shell, eyes closed, not eating, wheezing, fungus (ie white spots), for an example..The signs of a healthy turtle, bright eyes, very hard shell, loves to bask, loves to swim if aquatic, has a routine, eats his food, pellets, lettuces, cucumber etc. is active... you will know if he/she is happy and healthy....Hope this helps some, sincerely, Susan.