Negative Volume Help
 

Hi everyone, I'm meshing a pipe with fittings, with the main pipe having another pipe going through. I just need a little bit of help on how i should move the vertices to fix my negative volume problem. Tried the ICEM smoothing functions which created overlapping/penetrating elements. I think this should be simple fix but I do not know which vertex to move. :(

Attached are the pictures!

These slim elements on below of elbow are too long relatively to curvature.
Increase the number of elements or try to use as "Edit Edge > Link Edges", "Edit Edge > Split type".