Cheap Medium for seed starting

[Indyhydro]

I have been starting my seeds in my Aerogarden using the garden starter tray refill pack, but now they are out of stock.

I am growing the seeds hydroponically (they grow a lot quicker), then transferring to pots with soil, then into the ground.
Does anyone have ideas of basic household items that could be used? I thought of cotton balls or paper towels, but they would fall apart when trying to transfer to pots.

Thanks for any help.

Rob