The following is strangely named because it is freshwater only! It is the coolest shop in San Francisco - the tanks are all different and have home made lights, they're heavily planted, and the species selection is always very broad and interesting - lots of microrasboros, CPDs, endler's livebearers, exotic guppies, rare danios, cool cichlids, dwarf corys, pencilfish, killifish, discus raised WITHOUT hormones, all sorts of unusual things and new stuff all the time. The fish are virtually ALWAYS HEALTHY! Justin, the owner, is always there and gives very good advice plus his wife and daughter are there too and they are super nice. It's very down to earth and even won an award for being the best place for a cheap date in San Francisco one year.
Oh, additionally he likes you to bring in water to test, especially if you're a new customer. He won't sell unless your parameters are good. "I don't sell fish just for them to go die" he said to me once. He has fifty years experience in the field.
Oh, also, he sells a good, cheap bottled CO2 setup and will teach a number of ways of injecting it, how to make your own bubble counters that still look good, all kinds of good things.
Ocean Aquarium
20 Cedar St
San Francisco, CA 94109-6918
(415) 771-3206
Aqua Forest Aquarium is super-cool. It specializes in ADA nature aquarium stuff so they have all the fancy CO2 stuff, a great selection of plants, ADA brand tanks, filtration, planting tools, all sorts of great stuff. Their fish selection is picturesque and interesting - plus they're always healthy! Their stuff seems expensive to me, but the quality the best.
What I don't like are their fishnerd boy helpers. They act just like snotty computer nerd guys who work in electronic shops - not really friendly and sometimes it feels like they lord it over you with all their technical knowledge. But if you can overlook that, they are good sources of information.
Aqua Forest Aquarium
1718 Fillmore St
San Francisco, CA 94115-3130
(415) 929-8883