 What were the points for when there were 30 tries against?
CREATE TABLE table_810 (
    "Club" text,
    "Played" text,
    "Won" text,
    "Drawn" text,
    "Lost" text,
    "Points for" text,
    "Points against" text,
    "Tries for" text,
    "Tries against" text,
    "Try bonus" text,
    "Losing bonus" text,
    "Points" text
)
SELECT "Points for" FROM table_810 WHERE "Tries against" = '30'