That's good that he has grown a little. Happy to hear that he is active and not stressed as well as being content when you hold him. Good that he ate one cricket on his own in the feeder tank. Sounds like he isn't fond of being fed in a separate tank, that could be why he isn't eating much. About how many crickets are put into the feeder tank with him at a time? I'm wondering if he's overwhelmed by them. Over the yrs, I had tried several times to try to get my beardies to eat from feeding tanks but they wouldn't go for it so I ended up offering crickets 2 at a time and waited for them to eat them each time before adding more to his tank. They liked that much better and would chase the crickets around to be sure to catch them, so cute to watch. You might want to think about trying that as it's very important that he eat more crickets since he is so small.
Are you dusting the crickets with calcium 5 days a wk and with vitamins the other 2 days a wk? They need calcium especially to prevent metabolic bone disease and other health issues. A good
UVB light is very important too and the calcium & UVB work together to synthesize the right amount of calcium in their bodies. There are some UVB lights that aren't good & can actually be dangerous, so could you let us know if you have a
UVB light and if it's a coil, compact or fluorescent tube?
Since the tank temps affect their total health including appetite and digestion, could you tell us which type of thermometer you're using, a digital strip, round gauge (dial), temperature gun or digital thermometer with a long wire & probe end?
When you said that he spends most of his time on the warm side, do you mean right under the basking light or on the bottom of the warm side?
His is so adorable and has great coloring popping out already. All of us want him to put on some weight and length so you can enjoy him for many, many years. We can tell that you care for him very much. Babies are very particular with their needs so that's why we ask so many questions about everything and offer so much advise.