What is it you need/want to know? Big tank, cold water, if keeping more than one they must stay close in size or the larger ones will eat smaller ones... Good water quality very important and these are somewhat dirty animals, so lots of water changes are needed.
Be sure not to put additives in the water outside of water conditioner if at all possible. Most medications are deadly to these guys, so be sure to get help if you ever needs to medicate. Some fertilizers can burn their sensitive skin, so go easy on any ferts if you need to use them and don't pour directly into the tank (mix into clean water before adding it to the tank). Monitor pH closely. Low pH, for whatever reason (most common is due to high nitrate/lack of water changes) can cause open sores to develop on their bodies, similar to newts and salamanders. Keep their pH at least in the neutral range (7.0) Harder water is ok too, most tap water is suitable.
Axolotls are actually kind of boring. They are predators, but spend a lot of their time sitting idle and watching what is going on around them, just waiting for a good opportunity to catch prey. Axolotls are territorial so don't crowd them, they will fight.
They're not compatible with fish. The few types of fish that like the same water parameters as the axolotl are either a threat to the axolotl or at risk of being eaten by the axolotl.
Not sure what other info you're looking for??