Skimmers and main drains aren't competitors — they're complementary. A pool circulation system typically includes both, because each cleans a different layer of the water.
| Criteria | Skimmer | Main Drain |
|---|---|---|
| Suction point | Water surface (at surface level) | Pool floor (deepest point) |
| Primary function | Collecting surface leaves, dust and oil film | Bottom water circulation and sediment drainage |
| Safety requirement | Relatively low — a basket/lid is sufficient | High — anti-vortex grille and multiple drains required (see suction-entrapment risk) |
| Typical material | ABS plastic body and lid | ABS plastic or AISI 304/316 stainless grille |
Do you need both?
Yes — in a modern pool circulation design, skimmer and main drain work together: the skimmer catches surface debris before it reaches the filter, while the main drain circulates the bottom water layer and sediment.
A system relying only on a skimmer can leave bottom water stagnant with sediment buildup; one relying only on a main drain puts extra load on the filter from surface debris. Both should be sized against the pool's total water volume.
Browse related products
Skimmers & Covers, Main Drain Grilles