yah, the BTA continues to grow, tight mouth, feeds well, but he does not get nice and bubbly...I actually researched the issue a fair amount several months ago and it seems some of them just don't bubble up sometimes. it is kind of weird because when i got him he had beautiful bubbles but after the shift from the LFS tank to mine the bubbles never returned. if you have any thoughts as to how to encourage the bubbles to return i would love to hear them