use different types of flea meds at different times of year per recommendations. It has worked GREAT with our cats and dogs. We used to have MAJOR infestations of fleas now we oly get a few.
I wuld have t liiiike this:
14 gallon-tetras, glo fish danios and guppies
35 hex- barbs and maybe mollies and/or brstlense plec
45 gallon-angelfish, dojo loach
from there u can research and plan a stocking for the 45