auto skimmers and main drains

[Building my own]

Hi Gang
I'm going to start building an "L" shape pool this spring. What's the pros and cons of using auto skimmers that are connected from the main drains. Or take the mains back to the pump.This is going to be a 8 foot diving pool. I'm planning on 2 main drains 2 skimmers and 4 returns and one for the auto vac.
Thanks

[Pool Help]

Just a couple of comments.

We always plumb the main drain and skimmers on their own lines. That way we can always run the pool, even if we have to turn the skimmers off for maintenance or repairs.

Why have you chosen to put in 2 main drains? The main drain is usually used to empty the pool and we have never had the need for more than the one we put at the deepest point of the pool.

[Building my own]

With 2 main drains there is a less likelyhood of intrapment by a swimmer. It seems like cheap insurance. Any other thoughts on auto skimmer plumbing?
Thanks

[N7GTJ]

Mine was designed with 2 main drains just for that same reason. The second main drain is mounted on the deep ends wall. It is required here and must be at least 5' away from the drain on the bottom and opposite side from the skimmer.
I also am running 2 skimmers. It is almost an L shape design with a 9' deep end. I have pictures of it at http://www.pool.n7gtj.com
The biggest problem with an L shape is fitting the diving envelope. I could not have anything sticking into the pool area like a ladder, so I had to put in a love seat as an exit. If you do not add a diving board than the size can be anything you want, but add a diving platform and a new set of rules apply.

[barely a splash]

Sounds like you have a good plan -- 2 skimmers, 2 drains, 4 return inlets, 1 dedicated cleaner attachment port.
Note that hydraulic system should be designed with ALL elements in mind -- components like skimmers, drains, returns; pump size (gpm at x ft of head loss, not merely horsepower); filter size; and possibly most important of all, pipe size.
And, with regard to drains: split suction is always a good idea (in other words, using two drains teed together). Suction entrapment is not something to mess with. If using two skimmers, you would usually run maindrain lines off front port of skimmer. This implies you have four suction outlet pipes -- two for each skimmer, if using split suction. It's OK to put two pipes from separate skimmers under each drain cover, as long as you don't exceed the rated max flow of the cover.
Best of luck to you.