Sentry's Attacking Air?

[JustGreenz]

and it's getting really annoying bc there are no entities anywhere and it's making my frame rate drop I have to keep killing them all in creative bc they cause way too many problems, I don't wanna remove the mod bc it's a great mod but I will if I have to if my frames are dropping bc of too many entities.

Edit: there is nothing above or below the Sentry's.