Grapefruit trees

Question

Last year we had large grapefruit and the tree was loaded. This year are very small. What happened ?

Answer 1

Too much nitrogen fertilizer can inhibit fruit production and cause small fruit. Or, leaving too many fruit on the tree can cause each fruit to be small. In that case, they should be thinned. Other possibilities are here:
https://www.gardeningknowhow.com/edible/fruits/grapefruit/grapefruit-tree-not-producing.htm