American Flag Fish/other killifish

[Ponera]

Just out of curiosity, does anyone have experience with these?

I have them in an unheated 33 gallon paddletail newt tank and they are doing well, but I have read that they can be aggressive towards each other. I have a male and female that stick close together and have some moderate interest in breeding, it would seem, but not enough to do much more than flirt.

Is there a proper ratio for them? My tank is not very heavily planted (working on getting nitrates higher, this tank is SO understocked) but they do seem to prefer the open water.

I have also heard that some top dwelling killifish can have success in unheated (20C/70F) tanks. Is this accurate? If so, I'd like to get 3-6 of them. What species should I be targeting?

[TheOldSalt]

Pretty much any North American native topminnow will do fine in that tank.

Flagfish usually have a harem arrangement. One dominant male is best kept with a few females. Males will fight among themselves.

[Fishpunk]

I have not had any problems with J. floridae males fighting except when the dominant male was guarding eggs. He will drive away everything. They will nip fins, though mine have only nipped fins of other species.

They are not so easy to spawn, especially the first time. eggs are small, nearly impossible to see. They spawn in substrate, or at least mine did. I only had one fry survive. There is some disagreement on how to best breed them. Do your research if you are serious about it.

[Ponera]

I am thinking of snagging another few females, actually, as they do well in this tank and the newts completely ignore them.

Is a ratio of 3:1 good?

[Fishpunk]

My male:female ratio is 1:1 but the fish are still relatively young. Also, they share the tank with a number of juvenile sailfin mollies around the same size. They all hang out together and only get pushy when it's feeding time.

[TheOldSalt]

Flagfish are very interesting in that they will spawn in different ways. They just pick the method most appropriate to the situation.

[Fishpunk]

Yes, and my understanding is that spawn near the surface has a better survival rate than spawn on the substrate.

[TheOldSalt]

Really? Hadn't noticed. At any rate, they are easy to spawn and raise, as are most pupfish.

[Fishpunk]

That was what some of my research stated. However, as I said, mine spawned in some very young wisteria on the substrate at the bottom of a 46-gallon bowfront with about 18 inches of water overhead.