It seems viewers appreciated Detective Phil Fish (Abe Vigoda) more as an active member of the 12th Precinct on Barney Miller than they did when he retired and turned his house into a group home on Fish, which spent one calendar year on ABC (1977-8). If they really cared about Fish, he'd have stuck around on his own show longer.
Fish retired from the 12th after the 3rd season of Miller, and now, with help from wife Bernice (Florence Stanley) shepherded a group of foster children. Somewhere along the way, there was a disconnect between Fish and the audience, perhaps because of ABC moving the show to a different night or some other hitch.
After the series ended, Vigoda returned to Barney Miller for a guest-shot or two, and that was the last we'd see of Phil Fish. Todd Bridges (Loomis), who'd demonstrated some chemistry with Vigoda when he guested on season 1 of Miller, leading to his being cast on Fish, went on to Diff'rent Strokes, and, well, you know the rest of his story by now, I'm sure. Florence Stanley's last regular gig, I think, was the 80's sitcom, My Two Dads, with Greg Evigan (ex-BJ & The Bear).
Retrodan5 uploaded this promo for a syndicated run of Fish:
Edit: 8/20/15: Episodes are now available on YouTube. Here's a sample: