Using a continuous loop for tying a prussic is ok, but it is tedious to re-tie and it can bind up too tight. This takes more energy to loosen, and accelerates your fatigue in a tree.
Consider changing over to an eye-to-eye prussic. You can use the same rope, tie it onto the carabiner with the same "fishermans knot", and then you can use one of the more advanced friction hitches like these:
VT's: http://www.mytreelessons.com/user/VT variations.JPG
http://www.mytreelessons.com/user/Schwab Notes.jpg#WIDTH: 117px; HEIGHT: 189px
http://www.mytreelessons.com/user/Kleim-notes.jpg.jpeg
Distel Hitch | How to tie the Distel Hitch | Climbing Knots
Icicle Hitch | How to tie the Icicle Hitch Using the End | Boating Knots
Klemheist Knot | How to tie the Klemheist Knot | Climbing Knots
http://www.mytreelessons.com/photogallery/Knut & TK HItches.JPG
Consider changing over to an eye-to-eye prussic. You can use the same rope, tie it onto the carabiner with the same "fishermans knot", and then you can use one of the more advanced friction hitches like these:
VT's: http://www.mytreelessons.com/user/VT variations.JPG
http://www.mytreelessons.com/user/Schwab Notes.jpg#WIDTH: 117px; HEIGHT: 189px
http://www.mytreelessons.com/user/Kleim-notes.jpg.jpeg
Distel Hitch | How to tie the Distel Hitch | Climbing Knots
Icicle Hitch | How to tie the Icicle Hitch Using the End | Boating Knots
Klemheist Knot | How to tie the Klemheist Knot | Climbing Knots
http://www.mytreelessons.com/photogallery/Knut & TK HItches.JPG