Can anyone ID this (juvenile?) fish?

  • We are currently upgrading MFK. thanks! -neo
The only killifish I even see listed for PA is the banded killifish, so that makes it pretty straightfoward. I see no topminnows (also a type of killifish) listed.
 
Just a warning: Fundulus species get along great with one another when young, but can be extremely aggressive and territorial (within their own species) when mature. This seems to vary from species to species within the genus, so hopefully bandeds are one of the less aggressive ones. In any case, a low stocking density, lots of cover, and lots of tankmates will help.
 
Hmm. Thanks for the heads up. Right now the two of them are in with:

3 juvenile Bluegill (largest ~2.5", other about 1")
5 Blacknose Dace (largest ~3" down to about 1.5")
5 Emerald Shiners (all ~2")
1 male Odessa Barb (relic from my tropical tank)
1 male Checker Barb (same as above)
1 crawfish (~2")

Will they be okay with just the two of them? Or should I add another in an attempt to diffuse any potential aggression?

The bluegill are growing out in this tank, and once I can reliably sex them I will only keep one female.
 
How things work out will depend on the genders of the fish involved. Adding more will make it more likely that you'll end up with a pair, which is the most stable combination. I should add that if the fish are caught fairly small and grow up together they are less likely to fight.
 
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