void clearRow(int row) {
         for (int i = 0; i < COLUMNS; i++) {
            root.getChildren().remove(pseudoblock[i][row]);
            //pseudoblock[i][row] = null;
            //pseudoblock[i][row].setFill(Color.HOTPINK);
    }

root.getChildren().remove(pseudoblock[i][row]);

for (int c = 0; c < ROWS; c++){
            if (isFullRow(c)) {
                clearRow(c);

private boolean isFullRow(int row) {
    for (int i = 0; i < COLUMNS; i++) {
        if (pseudoblock[i][row] == null) {
            return false;
}
    }
    return true;
}