Lettuce nudibranch issue

[maroonclown65]

Tried to push my nudibranch down into the sand bed from the top of my glass cause I wanted him to be on the sand but he was immediately sucked into my powerhead, I turned it off promptly maybe a 6th of the nudibranchs body was chopped up however. He landed on a rock and immediately began moving around will he just regrow the missing part of his body? Tank is a mixed 18.5 gallon

 

[Cthulukelele]

Tried to push my nudibranch down into the sand bed from the top of my glass cause I wanted him to be on the sand but he was immediately sucked into my powerhead, I turned it off promptly maybe a 6th of the nudibranchs body was chopped up however. He landed on a rock and immediately began moving around will he just regrow the missing part of his body? Tank is a mixed 18.5 gallon

Lettuce nudis need very little to 0 flow to thrive. Even if it heals it will be dead in a week if this is already an issue.