Too many fruits can cause diarrhea in reptiles. The urates should be soft and solid white and the brown fecal matter should be well formed rather than runny. Diarrhea causes them to become dehydrated because they're losing too much water. I'd suggest limiting the amount of fruit your beardie eats and
bathe daily until the movements become more solid.
At 11 months old, he should still be eating quite a lot of insects so maybe you could try a bit more variety to peak his interest again. Good staples are silk worms, hornworms, butter worms, crickets, phoenix worms, roaches, etc. Wax worms are like beardie candy so maybe a few of those mixed in may get him hungry. Bee pollen sprinkled on food will sometimes help too. Calcium would just be once per day and only five days a week. On the two days a week when you aren't doing calcium, dust with vitamins.
Also, when reptiles go off their protein sometimes that's a sign of parasites, so you may want to get a fecal float done with a Vet. (Or in females a sign of impending egg laying, yours is a boy for sure, right?)
Hope this helps.
