[Suicide Junkie]

Colonists are freeze dried when in cargo.

Take a peek at your resupply depot facility; it generates 1000 supplies per turn.
You planet can store up a couple tens of thousands of supplies.

If you move a ship into the sector, the planet will give the ship whatever is available. In addition, the supply depot will remote distribute 500 points to ships elsewhere in the system.

If you are overburdening your homeworld's resupply depot, you may need to build more depots, or move your ships less.