What are approx row counts and distribution of data in the concerned tables and columns? Have you run EXPLAIN (query plan) to get the plan that will be executed and can you paste on https://explain.depesz.com/ and share the link that results?
Do you have an index on LOWER( c_pagealias ) on table t_ages?
Do you have an index on LOWER( c_id ) on table t_meners?
If temp_10032019020721_4470 is truly temp table, was it analyzed after creating/inserting/updating/deleting data last, so that the optimizer knows the number of distinct values, how many rows, most common values, etc?
