Thanks for the tip!
Well, index is now used but...
Limit (cost=264291.67..264291.75 rows=31 width=50)
-> Sort (cost=264291.67..264292.80 rows=453 width=50)
Sort Key: added
-> Bitmap Heap Scan on feed (cost=1850.99..264278.18 rows=453 width=50)
Recheck Cond: ((active_id = user_id) AND (type = 1))
Filter: ((user_id + 0) = 7)
-> Bitmap Index Scan on feed_user_id_added_idx2 (cost=0.00..1850.88 rows=90631 width=0)