TF-2 is akaline just like TF-4 or TF-3. I thought that was the reason for the lack of HCA. The stuff lasts forever. I throw it out and the fixer will still be fixing film in the same time periods that it did when new. But will have started to yellow so out it goes.
Buy a big bag of Sodium sulfite [say 10lbs. ] Everything uses it. The other stuff is more related to how much you use it. Check ebay for a seller called something like surebet2. His 10lb specials are pretty good.