i am sure i don't have a light issue -- 1 400w mh - 2 250w mh - 2 110w atinic vho's - and its on the sand - no blockage from light in a 120 gal - Could be wrong on the happiness being bloated but when everything in my tank is happy they are all out and flowing - when levels are off a bit no-one is out and the brain is deflated - just my observation in my own tank
Every day is a learning experiance so if someone knows the actual behaviour of a brain please share.
Cheers
Rich