just do it ... as fast and clean as you can .. get it done.. repot it in moistened media... and set it in full shade if outside ... and then learn how to water it properly in your new media and pot ..

i spent .. aka.. wasted.. to many hours of my life stressing on all this.. and frankly .. all my fear and hesitation were worse for the process.. rather than just getting it done.. including root pruning .. and get the plant reset ..

and if there are any severe winding roots.. cut them back ....

there is a reason these are common houseplant.. and that is they are easy to deal with [perhaps but for size]...

to repeat.. jest do it.. and get it over with ..

ken

If you have a granular soil at the bottom and potting soil above that, treat it like any other plant that needs a full repot, but skip the self-watering feature unless you just can't do without it. The type of set-up you're using now ensures all dissolved solids (salts) from fertilizer solutions and tapwater remain in the grow medium where they build-up to levels that can severely limit the plant. It's better to water from the top and flush the medium when you water. Flushing the soil regularly ensures salts cannot build up, and it ensures the ratio of nutrients, each to the others, does not quickly become badly skewed and cause problems, the most common of which are antagonistic deficiencies which occur when to much of nutrient A limits uptake of nutrient B (and/or others).

Roots are very forgiving, as long as you don't allow them to dry out while you're working on them. This is a Ficus benjamina repot:

As you can see, more than 90% of the roots were removed, some of them as large as a quarter (of a dollar). I'm not recommending you do something so radical, only illustrating how forgiving roots actually are.

Let me know if you need guidance re the repotting, monitoring moisture levels, or putting an effective fertilizing regimen in place.

Al

Thank you both! I'll just go for it and repot, and switch to a regular pot. I only had this in a self-watering pot because it was my first houseplant and I nearly killed it when I first got it, but I'm confident I don't need such a pot anymore :)

You might find this helpful. (click link)

Al