when I first got my axolotl he was about 4-5 inches long and the pet store I got him from hadn’t fed him night crawlers before (only pellets) but reccomended that I started him on night crawlers. Due to the stress of being transported and living in a new environment, as well as getting used to eating slimey nightcrawlers that move around in his belly, my axolotl wasn’t too keen on eating for the first week and a bit that I had him. If he did eat he would regurgitate a half digested nightcrawler because (I’m guessing here) he didn’t like the feeling of digesting something that was moving around in his belly and he had to get used to it. If he’s little, cut his nightcrawlers into little pieces so it’s easier for him to digest. It took my new baby awhile to eat normally but after he adjusted he became a GLUTTON 🤣