Questions:
1. How big is your tank?- Whist small tanks can work for more than one axie in the short to medium term, realistically, you should be looking at a square foot of tank floor OR 40L per critter to avoid major problems long term and so you are not be doing a full-on balancing act (trust me, been there, done that, would rather NOT do it again)
2. How old is Zendora? if she's really young (as in, 2 inches-3 inches) she may be more inclined towards snapping at anyone else you introduce.
3. How old is the other axie? Are they around the same size? If there's a big size difference, the larger could have a go at eating the smaller.
Some things to do if you clear all the above questions:
Add in HEAPS of hides and sight blocks- old terracotta pots, cut up PVC pipes, lots and lots of plants- all of which will keep your axies happy and give them space to chill out.
Get a really good filter- remember that the flow needs to be as low as humanly possible to keep your axies happy and their gills nice and fluffy. If you can establish it with media from another TRUSTED filter, do so. nothing worse than losing a pet to a disease, especially when you're really attached to them.
Lots of water changes- especially at the start- 10-20% of the tank every day or two whilst your tank cycles.
Feed- often in the beginning, so you don't get into the scenario of "Hmm...Iz hungry, youz is FOOD!!".
Also, beware that axies are addictive- i started with three and am now at 11 adults and a heap of babies and about to go to a six foot tank
