Is Bleach episode 225 filler?
Canon No, episode 225 of Bleach is canon.
#225
Vice-Captains Annihilated! The Terrifying Demonic Beast
副隊長全滅!恐怖の妖獣
Aired 23 Jun 2009
Mochibayo compiled this list from MyAnimeList's labels, because MyAnimeList's episode data is not reaching us at the moment.