Where are you in Los Angeles? If you live east of the 405 I'm going to be a little assertive in suggesting your reconsider the choice for Marathon. Marathon needs much cooler weather than you can promise when you move inland away from the cool afternoon winds at the beach. It will certainly grow east of El Monte, but the watering requirement makes it wrong for a drought stricken area. I could make an argument that 30 years of planting Marathon types of grass from Bakersfield to Calexico and Rincon to Blythe was the sole reason California is in this predicament.

When did you seed? What time of year?

How did you prepare the area for reseeding?

How are you watering now? How often and for how long?

Marathon I, II, or III are the only seeds that will match what you have. You need to know which one you have. They come in slow growing, very slow growing, and ultra slow growing, I, II, and III.