I've had two AFT's for around 7-8 years and until recently my fat tails have gotten along when feeding. About half a year ago one of my fat tails bit the other one when the other lizard got a cricket they also had eyes for. I had to gently pry them apart, and I have been cautious when feeding them since. Though there have been a few moments I'll walk by their tank and hear intense rustling and find one or both of them biting each other, which has made me extremely worried. I provide them with four different hides and two water dishes to keep up humidity and have that constant water resource around. Recently, a friend told me I'm not supposed to house two adult fat tails together, which was news to me. My one lizard has visible healed injuries, one is a scar on one of her eyelids and now she has a bump on the side of her tail. I believe my one lizard bit her tail and it has slowly grown these couple of weeks, I gave her a week to see if the swelling would go down but it did not. Now I'm not sure if she was bitten or if something more is going on, there is no broken skin, and there was never any bleeding. The lump looks like her normal tail and her tail looks a bit off. She seems happy, and without any pain in that spot, so I don't know if I'm overreacting or if I need to get her checked out. She's eating very well, I feed them both crickets dusted with calcium, D3, and multivitamins, with the occasional dubia roaches. I also recently bought them some wax worms to try and they absolutely love them. They only seem to bite each other during meal times and few other random occurrences (about 4 times in this time span). I separate them while feeding now, which has lessened these occurrences significantly. I'm considering putting a barrier in the middle of my tank to permanently separate them but I'm not sure if it will give them both enough space. If anyone has any suggestions or has seen or experienced anything similar please don't hesitate to comment or give input. I'll add a picture of her tail below to hopefully help. I'm not sure what to think so I may go to the herp vet if I can't find answers soon.