One good way to get started fish it not to buy fish or eggs, fry. These can be scooped out on a fishroom visit whereas it's uncommon to find fry in ads as they don't as well as fish or eggs. The upside is they're cheaper, per fish, than any other way of buying eggs. Often a hatch of long term annual eggs is so big that they really can't all be raised. Sometimes these can even be free as the killifan is eager to have smaller herd to look after and thus come closed to the lofty ideal of raising 100% of what was hatched. Any the fun isn't over once fry grow there's a sibling cannibal issue to address among the fastest growing fish, either these or all the smaller ones, must be relocated. The breeder will often keep some or all of these as they're put in other tanks for growing out,and this is abot the stage in life you want to acquire fish at all things being equal.