I've never fished the Malihini, though I've fished yellowtail off probably a dozen other boats out of San Diego (the 3 landings there are next door to each other, and the boats fish the same areas), and managed anywhere from nothing to limits plus for the boat.
The bait will be sardines or anchovies, or if you're lucky, live squid. Or if there's nothing available but small anchovies, you may have to catch mackerel for bait.
The yellowtail bite at the Coronado islands or on the Mexican coast (or local areas along the coast) varies considerably -- sometimes it's dead even in midsummer; sometimes it's wide open, depending on all sorts of factors (water temp, bait available, time of year, the fishing gods). In addition, sometimes the albacore or yellowfin tuna come in close enough for a 3/4 day boat, so the boats run offshore instead of fishing the coast for yellowtail. The boat's skipper will choose what he thinks will result in the best catch.
When planning your trip, check the current catch counts so you'll know when the bite is on. For the landings in general (the Malihini is at H&M, the other landings are Fisherman's and Point Loma, though these counts include the overnight boat counts which are generally better) check http://www.976tuna.com/e107_plugins/landing/wrapup.php.
For individual boat counts, check http://www.sportfishingreport.com/pages/landingdetail.php?landing_id=21 for H&M Landing,
http://www.sportfishingreport.com/pages/boatdetail.php?boat_id=157 for the Malihini.  | 
Linear Mode
