I would have put it in a bigger pot without the insert. That tree will very soon outgrow the pot (and insert) you put it in. It needs a wider and deeper pot.

Regarding the insert; this is what I found on the manufacturer's website: But with less soil, the roots will be confined forcing nutrients back
into your plants where they belong, producing healthier plants with
bigger blooms .......... This is news to me. I don't believe it. In fact, confining a plant's roots is detrimental to the plant's health!

Vladimir I can not use bigger pots right now or I will not be able to get it in the house for winter. This is already a big pot about 24". i might have to repot next year and the roots will be trimmed back.

btw, citrus in general are not going deep with their roots and can tolerate shallower pots. The moro had the root system spread in width but not so much deep. To be honest, this was a surpirse to me. The other advantage for using is that there is an airspace and not direct contact with the cold floor in winter. Plus I can have them sit in the pot bottom with water to regulate humidity in winter without roots in direct contact. We will see how this goes :) Will have some trees planted with this and some trees without.

OK I can see why you chose what you did.