I agree with most all what Peter said- I'm just going to drop my own two cents anyways (oh, and for the person asking distances- just google map it, all the stores should show up)
AquaSD- Obviously a really nice reefing store- His priority is mostly on livestock, and corals more than anything else so real sweet for that. Super friendly and helpful staff, really clean shop, clean tanks, and real nice looking systems everywhere. Limited but adequate selection of fish and drygoods, but will bring in pretty much anything you ask for at competitive prices. Main place I go anymore as Will has always treated me really great, never minds me asking him to make frags of stuff to bring it down into my pricing range, and is always willing to help out like I'd expect from a fellow hobbyist more than a shop owner. Also it's always fun to annoy Jojo (one of his staff) so worth going to just for that. Plus his shop is next to Arby's, and I have a horrible addiction to Arby's, so I can make the excuse of going to Arby's and just "stopping in" to AquaSD.
Pet Kingdom- Largest independent pet shop (fish/reptiles/small animals/occasionally kittens) in San Diego, so worth going to just to look around. They have more variety of reptiles than the San Diego Zoo, so that's should tell ya about that :tongue: Saltwater wise, usually pretty good, big fish system (could use some upgrading like nice lighting on the fish, etc) big coral and invert systems, and a nice SPS system. Only downside is occasionally the SPS system has some disease problems (AEFW and Redbugs) but typically they're good about catching it and trying to fix it quickly.
Aquatic Warehouse- A shop that tries to run as a mini-wholesaler setup, with very similar systems. Tend to be a little higher priced on livestock, but cheap on dry goods, with a very sales-motivated staff (think used car type sales people.) if you ignore them it's not bad though, and worth looking around. Tend to stock the same fish on a regular basis, so not a huge reason to revisit often. I know a lot of locals like their corals, but I've never really enjoyed their coral system or the way it views. Always just looks a bit "grungy" overall-not dirty, just something that doesn't make the corals look appealing to me.
Octopus Garden- I've been there three times, and all three times there was a random person hanging out who apparently was the one working there. Never been in there when the lights are actually turned on (he turns them off most of the time to save on power bill is what I've heard, but not sure) on the majority of the reef/fish tanks. Also I didn't see many prices, which means I would have had to ask the guy who was obviously annoyed I was in the shop for help on every single thing I was curious about, so I pretty much didn't bother. That said the owner is supposedly really awesome and friendly and helpful- I guess I've just never stopped in when it was him in the shop
Fountains- They've been around for a long time, and I have a feeling this is the shop that Petco/Petsmart ripped off for their aquatic sections blueprints. Purely a fish store with fresh and saltwater, pretty good selection of dry goods and a decent amount of livestock. I've only visited as a customer a few times, and never bought anything. Nothing bad, just nothing amazing that made me want to pick it up. Fish room is unlit with just the tanks lit to get people to focus on the fish- for me I didn't like it as it just seemed weird.
Petco- I know you asked for LFS's, but the Carmel Valley location has a manager who tries to operate the fish section like a LFS would, is extremely helpful/knowledgable and actually has his store as a sponsor on a few of the local reefing forums, occasionally posting when they get cool stuff. Worth stopping by if you're in that area.
Others- there's a bunch of ones in south county, north county, and a couple out east that I don't know of- if you're going to those areas do some searching on Yelp and might be worth stopping in some of those random ones.