Stock the tank with a lot of plants for the female(s) to hide in. Floating plants are of great benefit because they make it easeier for the male to keep his bubble nest intact.
(the male; to keep; his bubble nest) (the female; to hide; L:in) (they; make; it easeier for the male to keep his bubble nest intact)
the male the female they
to keep to hide make
his bubble nest
L:in
it easeier for the male to keep his bubble nest intact