Started as 1 head when I first bought the tank 2 years ago and havent found out what the specific name is still lol. I took the picture during a water change, so it's pretty retracted usually 6x the length.
https://www.reddit.com/submit/?source_id=t3_1q1m4vj
https://www.reddit.com/submit/?source_id=t3_1q1m4vj
