Killifish

I have been keeping killies for a number of years, and currently have several species of Nothobranchius. I would suggest against those annulatus...they are fairly short-lived and a bit fragile. Go with some Nothos to start, they are inexpensive, readily available, and easy to keep and breed.
 
Toirtis- which of the Nothos do well with flake food IYE?
 
only thing I would add to what the others have said is that if you've never kept them before try to get your hands on semi-annual species as opposed to annuals (annuals require some breeding skills to maintain stock for more than a year). the aka.org beginner guide should give you all the information you need to make an educated decision on which ones to get.
 
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