Hello,
definitely P.delhezi (and in the background P.ornatipinnis) ...
A good decision to keep them with water plants (also fast growing ones) - especially if the baby bichirs are breathing with their external gils it is important to keep the oxygene in the water stable ... plants will do a good job there.
It's also fine that the plants you are keeping (sorry i don't know the english word for them) are very good nitrate killers - also good friends in keeping your water clean and healthy ... young bichirs with external gills are much more sensible than those with retarded external gills.
Greetings
Uwe