I sit the used, full pot in a trash can and let it dry completely.
When I need the pot again. I pull the dry root ball out. Add some fresh coco and I rinse the pot with the old coco in it. Using the garden hose. Really flushed well and drained.
Them I take the pot and stick it in an ice chest. Which is filled with a times 3 dose of Cal-Mag in RO water. Its soaked for about two days. No rinse after that.
Then the prepared pots go in the grow room about 2-3 days before a sprouted seed is stuck in it. Treated with Azamax and BTI during this time. Allowed to warm up.
That's it. After the grow...back in the trash can. Dry, pull, rinse, soak, and repeat.
I don't care if the fabric pot stays ugly.