I have a male 25 year old RES whom I have been feeding Nutrafin pellets since I got him. He is a very greedy RES and will readily gobble up the pellets. However, for about 1 week now he has been refusing to eat the pellets. He just look at the pellets, sniff at them and swipe them away!
My RES looks generally healthy. No fungus, respiratory or eye infection symptoms that I can see from. In fact, he is more hyperactive than before. Because he has not been eating, he is not pooping well though. It used to be long "trunk like" poop but it is more "grain like" now. No visible worms or parasites in his poop. There is no sand or gravels in his tank so it is unlikely that he is impacted. I tried to soak him in warm water for up to 20min each day but he is still not eating any pellets.
His living condition is clean- I clean his tank and change the water everyday. Once every month, I will bathe him. We live in a tropical country, so low temperatures and winters are non-existant.
I am pretty worried because he is so senior. What should I do? Is this a phase or should I take him to the vet? He looks super normal except not eating though.
Thank you!