Change the number of default rows in a nx1 gallery

Because of the way I wish to display information from my dataset, I have a grid gallery in a n x 1 format.

a 1 column grid of variable sized rows.

Right now the default number displayed is 9 or 10 - how can I change this so that I get all the “rows” - basically all the elements in my dataset displayed - probably less than 20 without having to have the “show more” invoked in order to see more rows.

Can I alter this?

Thanks! Deborah