Currently, when an ELE is used for the first time in a breeding, it becomes recorded under the "Fixed," list of ELEs, rather than the unused list, which is located in the marketplace records.
This is the list:
Kyrit wrote:Fixed (Used) Eternal Love Elixirs:
Azura Rayume; Arthur
BaalsBaby; Aiden
BaalsBaby; Lord Baal
BaalsBaby; Noir
Flame 1; Aphrodite
Kitsumi Mahon; Saphia Morpho
Kodai; Kuruijini
Krypto; Jorrmundde
Krypto; Thanatos
MidnightDraconia; Grelle
MidnightDraconia; Raito
MidnightDraconia; Sable
MillietheWarrior; Asher
MillietheWarrior; Axe
Mojave; Reno
Moofius; Zed
MythicDusk; Akkia
Nyxia; Cecil
Shieba; Darsis
Shieba; Hina
Shieba; Divina Astraea
Shieba; Gaena
Shieba; Lyria
Shieba; Nalana
Shieba; Naryu
Shieba; Talan
Shieba; Velia
Shieba; Omoikane
Shrewdberry; Crimson
Silverin: CD
Silverin: Eric
Silverin; Raven
SpringsSong 1; Kanika
Talcen; Sedimus
As you can see, the list contains the name of the pet it was used on, as well as the owner of said pet. When a pet with a fixed ELE is traded, a trade note would also have to be mentioned in the Marketplace trade notes.
Although, the idea of listing the image might prove more useful than just names, in the event of name changes.