Plugging holes in the pots

[bogdan]

I went today and bought some mini office trash cans from our version of dollar store and paid almost 2$ a piece for a 1,3 L version (44 oz). It is semi-transparent white, so less chances of algae, hopefully. I need at least 150$ worth of these and who knows if they run out of them.

I do have quite a lot of regular orchid pots and would like to use them for s/h but I want them to have an internal reservoir, unlike last time when I grew a lot of algae in the trays in which the pots were kept. Do you have any recommendation on how to plug the multitude of drainage holes that these pots have? I was thinking bathroom silicone but wouldn't that give way due to the heavy LECA pressing on it?

Thank you