Please rate models/profiles - helps both creators and you via points as well as feedback or gratitude! :)

Printed self watering plant pot https://makerworld.com/en/models/122222#profileId-131680 (actually not exactly this one, but other one that was exactly the same, but got deleted, probably some duplicate).

Same one here: https://makerworld.com/en/models/372949?from=search

Floater is 23mm wide, fits exactly in the hole and shows if there is enough water. Height is ~9cm, when there is no water, it's almost fully submerged

Fusion 360 file included so you can easily modify it to suit your needs :)