BTA tips get fat after feeding

Just thought that was interesting. Is this normal?
I recently purchased an entire livestock and rock from an established 90 gallon reef tank off of craigs list, and included were 3 BTA's.

For a couple days I tried feeding them various meaty foods and today we gave each a silverside. about 3 hours after feeding all 4 BTA's in my tank started showing larger bubble tips. Is this to show me they are full or something else.

Prior to feeding the tentacles were all long and straight.

 

Your bubble tip is happy. That's why they're called bubble tips. They can deflate to the point where they have hardly any shape left, but the foot will still be attached. Then they puff back up - they expell waste that way. Supplemental feeding is good practice, just don't overfeed.

 

When a bta stretches out he is trying to get food. Its their way of covering more area. Fat tips mean happy bta. I never feed mine till it stretches out.

 

is this too stretched for a BTA ? (ya think !)