Streaks on GBTA (Pics)

[Vitaly]

I occassionally see these dark streaks along the body of my GBTA. They are not always present. Does anyone know for certain what they may be. My guess is that it is part of the digestive system of the GBTA (streaks form from a bolus of food)?

Thanks for you comments.

 

[SEAFLOWERS]

Mine has the same thing happen after being fed.

 

[GSMguy]

stringy stuff inside the anemone?

ive seen that on mine many times