I'm looking to buy either Endler livebearers or Heterandria Formosa (Least Killifish?) to breed in my 10 gallon tank. Which of the two species is the smallest? Which female is the smallest?

I also have Red Cherry Shrimp in my 10 gallon tank; which fish species is the least likely to harm the adults and the shrimplets?

Are there any other smaller fish that I may stock my tank with?

How do I deal with too much in-breeding. I have been told to introduce new stocks of fish. What other techniques are there? Should I separate the two fish into two different populations?

What is the best fish for my scenario?

Oi vay. Lot's of questions.
THANKS!

Which is better is to the taste of the person keeping them. H. Formosa females are smaller than the Endler’s female and are the smaller species of fish overall. The Endlers males are more colorful.

For a 10 gallon tank with cherry shrimp I would say that the shrimp will do better with the H. Formosa. The Endlers will not eat the adult shrimp but will eat the smaller shrimps. I don’t know if the H. Formosa will eat small shrimp or not but should not be a problem for the adult shrimp which will be the same size as the fish.

I wouldn’t think that you need to worry about inbreeding if you start with a small group of 6-10 fish. The fancy strains of fish that you see have been inbred for many generations to lock in their different patterns and while maybe not as vigorous as their wild counterparts don’t seem to suffer unduly from the inbreeding.

A ten gallon tank is not big enough to keep male and female endlers, whereas ALA has a member who has kept H. formosa in a 5-gallon tank continuously for a decade.

I think that at 10 gallon tank is plenty of room for a pair of Endlers. Females are less than 2" total lenghth and males come in around 1". Put a couple males and 3 or 4 females in a nice planted tank and they will look great.

The fry will need to be removed but at some point fry always need to be removed.

Heterandria formosa. The females are about the size of a fingernail while the males are smaller. They don't have a tendency to eat their fry and they always look cool.

Endlers don't eat their fry if they are feed properly. I started with 4 pairs of endlers in a 46-gallon tank. Six months later I had over five hundred fish in there. They are extremely prolific. Plus, the females will be endlessly harassed in a 10-gallon tank.

Thanks everyone! All the tips were really helpful. If anyone is curious, I decided to get Least Killifish over endlers. Maybe someday I'll get endlers in a bigger tank.

I think you made the right choice, and I do hope you get those Endlers eventually.

I had great success with endlers with very little maintenance. I placed them in a 55 gal tank on the porch then one night the racoons got them all but fry. I caught the few fry there were left and in a couple months overr a hundred again. I never seperated fry and did not even give much room for fry to hide. I venetually gave them to a student at Berkly and he fell in love with them.
gerard94114@yahoo.com

I know that your decision has already been made. I just wanted to say that I keep both Endlers and Formosa, and I placed a dozen cherry shrimp in with each of them. The shrimp in with the Endlers have reproduced many times. If the fish are eating any, it's not enough. The shrimp from the formosa tank disappeared. I replaced them with a dozen bumblebee shrimp and they also disappeared. Now I just toss the extras into the formosa tank from the Endler tank when that population gets too dense. I don't know how they eat the shrimp, but either they are, or I have an invisible shrimp teleporter in there ;p