Hi @GoldenAspen
Going to 12.5mg would be better than alternate days. Alternate day dosing is generally a bad idea. I'm glad you felt okay dropping to 25mg. How is the dizziness?
The fact that you've only been taking it six months is in your favour, it's usually easier to taper when you haven't been on it for too long.
I have no personal experience with Sertraline but a 50% dose reduction to 12.5mg might be too much for your system to handle. A hyperbolic taper recommends a 10% cut from your current dose. You can read about it under Resources on this site.
Good luck!
Trintellix — 15mg — 4 years, 9 months — researching taper | Risperdal — 0.25mg — 4 years, 9 months — actively tapering | Depakine — 1000mg — 12 years — supporting others | with clinician