How long has it been in this “little dish” and how long have you had your Bonsai? How often do you fertilize and with what? Do you prune it back?
Bonsai trees do get rootbound eventually though they generally like to be slightly rootbound. If you’ve had this Bonsai for a while (i.e. longer than two years) it may need a larger pot. Get one that’s only one size larger and put a nice dirt in with it (I use a miracle gro dirt-I know, I know it’s bad but my plants love the darn stuff). Fertilize about once a month. I use a great sea weed fertilizer on my Bonsai trees but I know some people who use that M word stuff very dilute and their trees are doing quite well.
Most Bonsai trees need a lot of sun but make sure it’s not getting overheated. When they’re in those little pots it doesn’t take very long for them to get hot and dry.
Gotta cut that puppy back once a year (I do all my pruning and repotting in the spring but you’ve got an emergency here). You want to prune for shape and strength so anything that’s robbing strength from the main system has to go and anything that detracts from the overall shape the tree is trying to achieve is excess baggage.

my Grandmother, (who rivives all of my nearly dead plants) has several Bonsai’s which just keep growing and growing. When I ask her why, she told me that she only, EVER gives then drinking water. NEVER tap water. I would have never guessed that.

Hundreds of species are made into bonsai designs, and all the advice anyone gives you is WORTHLESS until you know the species of tree. If you don’t know the species, you’re welcome to send me a photo at: and then I can send you care instructions. You might also want to read the Bonsai Care page of my website: