Stand alone tweeter?

Power treatment can definitely help the sound of your system, don't discount it too easily.

What acoustic treatments have you tried and where?

Is it possible that different interconnects would alter the harshness of your tweeter?

I believe I would also contact the manufactorer of the spealers and ask them for suggestions.

@gondo101

Imagine my surprise when I checked your system and saw Totem Forests listed. I have had these same speakers for around 10 years now and am very familiar with their sonics. I am sympathetic to your finding their treble can be harsh. That metal dome tweeter helps with resolution and imaging but - esp. w/certain badly (mastered?) material - can be hard on the ears. I love the Forests and have spent a lot of time working to tame that upper frequency "bite". I am not dismissing treatments for your power that have been suggested. I haven’t really explored this area. Also, I don’t know your electronics and can’t speak to how well or not these match up to the Forests. I don’t have time right now to investigate them.

Here are things I feel contributed to a MUCH more listenable experience with them on a almost ALL the recordings I have (by the way, my system is listed so "a picture is worth a thousand words):
Room treatment
Electronics - Hegel H200 amp (much "warmer" and forgiving than EL34 tube mono blocks!) and Gungnir MB DAC.
More power - wpc adequate to drive the Forests might be way less than needed for best sound and I believe this might extend to treble "sweetness" or lack thereof.
Ripping CDs and playback via Schiit Gungnir MB from Auralic Aries Mini
(don’t underestimate the potential contribution of jitter to that HF pain)
Cabling! I’m well aware of the "don’t use cables as tone controls" orthodoxy. The CD/SACD player I use (TEAC CD3000) was highly resolving but on some CDs, almost unlistenable. Cardas 300B Twinlink SE and Cabledyne Copper Reference XLRs provided a big improvement. Cardas Golden Reference between preamp and amp. Clear Day Double Shotguns and, more recently, Cardas Parsec speaker cables have helped a lot too. Try connecting your speaker cable to the lower speaker binding posts and see if you hear an improvement.

Those are the main points. If anything else comes to mind, I’ll post again later. I’m sure you will be getting advice to sell the Forests though I think they have much to offer with properly managed HF. Good luck!

Unfortunately adding a super tweeter will not smooth out the tweeter that you currently have, it will only extend the top end and could actually add to the frequencies that bother you... 
I'm sorry if you said, but I didn't see it.  What speakers are you using?  Are they as ghosthouse posted indeed Totem Forest?  I

I'll take a look and see if I can offer some practical advise,
Tim

Your Tron stages have a relaxed sound, and I would imagine so do your Totems. If the Trons are new they do take time to settle down. Otherwise, you can try plugging your power amp directly into the wall if you currently have them plugged into your conditioner. Did something change, so your tweeter started sounding harsh, or have you been working on your system over time to resolve the harshness?
Kenny