One using tanks a lot (5)
I believe the answer is:
diver
(Other definitions for diver that I've seen before include "Person operating under water" , "Water bird" , "Grebe maybe" , "Cheating footballer" , "Underwater worker" .)
I believe the answer is:
diver
(Other definitions for diver that I've seen before include "Person operating under water" , "Water bird" , "Grebe maybe" , "Cheating footballer" , "Underwater worker" .)