How about some Indian Almond Leaves or blackwater extract to pamper him? Bettas like slightly acidic water, and Indian Almond Leaves naturally brings down the pH to levels found in bettas' natural habitat. It will greatly help to heal his fins and make him feel good overall. You could either immerse a leaf in the water or make an extract by boiling several leaves (in a stoneware pot, not metal) so that you could keep it in the fridge and control the amount that goes into the tank during each water change.
For expedited shipping, you could order them from joshsfrogs.com, but for the long term I'd buy Amy Lim's Grade A+ from ebay. I've ordered from both and Amy's is larger and better quality.
Or you could just buy bottled blackwater extract instead of IAL's:
Hope this helps!