I agree that Pet Cetera in Davis is good. A nice older couple run it and keep real healthy fish in there. Admittedly limited selection, but still good for what it is. I saw cardinal tetras in there before for $1.99/ea and real healthy looking. The Ace Hardware in Davis used to have a good fish section and a real knowledgable guy working it. That was back when I was in college (late 90s) though.
Does anyone know where Exotic Aquarium moved to? I haven't been in there since they were on Florin(South Sac) across from Home Depot. I know they were moving b/c the tanks were starting to look pretty bare and one of the guys told me, but I forgot
Fish Planet would be good for me. It's even closer to me than Capital Aq, which is about 10-12 minutes.