why is my walking bumble bee toad not so active until I put fruit flies in?

[Taryn Bidwellnation]

I have him in a 5 gallon with live plants, wood, coconut moss in s coconut, gravel on the bottom, bark on top, a pool, and frog moss. Its temp is 80F and humidity 70%. He usually stays in one spot and is all alone.

What should i do

Get him a friend with my birthday money(hes 40$)?

or get a 10 gallon?