He seems to be averaging about 35g a month. His diet consists of mostly Dubia and Hissers. He goes on a strike for one type and then readily takes the other. He eats about 1-3 a day. Once in a while he skips a day. He gets the occasional Hornworm, Large grasshopper, Mantis. After eating anything like a Mantis I check his gums and the inside of his mouth as best I can without stressing him. He's now 20 months.
I gut load my feeders a mix of cricket crack and bug burger. Twice a week they get fresh veggies. My feeders are in colonies so all that gut loading is also translating into simply healthy feeders. Personally I know from experience that is a huge thing if a person can pull it off. I could never do it with crickets, dang things always die.
Supplementation consists of straight calcium six days a week. One day a week I use Repashy medium D3 and that only goes lightly on a single feeder. Twice a month he gets a few lightly dusted with Repashy Multivitamin and Mineral supplement. No magic, just consistency.
Lighting, many know I picked up a monster quad light fixture from Todd over at Light Your Reptiles, money well spent. Atlas rarely goes to the top of his cage to bask, I even offered him a spotlight sometimes but he never wanted it. However the plants create varying shadows and the exposure to the lights will vary too. Atlas seems to walk around until he's comfortable and then he just enjoys his spot. His cage is large enough to allow him choices and like mosrt animals, he makes the choice that feels right to him.
So, it's a combination of diet, lighting, temps, and a lot of water, that is letting him grown like a weed. I'm hoping that by the time he is 5 years old he'll be done growing. His current cage space is only 60% of what that entire cage actually is so when he's ready I'll open up the rest of it for him.
Sometime in the next two years, I'll be looking for a lady for him. It's on my bucket list to at least hatch one Parson.