Heterandria formosa

These little guys are definitely little! I was hard pressed to find a tank to place my one pair. I didn't realize how small they were until I needed to put them in a tank where they wouldn't be eaten by my other tank residents.

The male was only a 1/2" in length at most and looked like a newly born livebearer (Guppy) himself! The female was almost 3/4" long and very plump.

I decided to place them in a 20-gallon tank that had a good thick layer of gravel to anchor several live plants. (Onion-like. These plants grow quite rapidly.)

The only other fish in this tank were my Corydoras pygmaeus.

Well, I placed my pair of formosa's in this tank with the Corydoras pygmaeus. The next day I saw several small "swimmers". (I refer to all fish that don't cling to the glass or stay at the bottom of the tank as "swimmers". I knew these swimmers weren't C. pygmaeus because they were to large, compared to pygmaeus fry that is, to be pygmaeus. That left the formosa.

In the mean time, I moved. I really didn't pay any attention to the occupants of this tank for the next 3 months.

I noticed I had enough fry to turn in for the BAP program. (I belonged to the SACRAMENTO AQUARIUM SOCIETY and one of their programs is the Breeders Award Program.)

But, how was I to write an article? Everyone I talked to said these formosa have only a couple of fry a month. OK. But, I wanted to know for myself.

I took my main female and a male and placed them into a half gallon plastic container with a couple strands of anacharis. The plants were to help protect the fry from their parents. Most livebearers are quite comfortable eating their own fry without any quilt.

Two days later I found 2 fry at the surface. I netted them out and placed them into a net basket I had hanging in my Killie community tank awaiting their arrival. Two days later I scooped out two more fry; 3 days later two more fry; 5 days later one fry; 7 days later four fry; 9 days later one fry; and 7 days later another six fry! I was truly surprised at getting the 6 fry at one time.

I did this over a 30 day period and got 18 fry total. Now I knew. My female wasn't consistent as to how far apart she delivered or to the number of fry she produced each time.

My water hardness was 80 ppm and my pH was 7.2 The temperature was maintained at a room temperature of 73° F.

Another note I observed was neither the male nor the female ate the fry. I was happy about this. I then placed the fry and parents back into their own tank.

These are really interesting little fish. I fed both the parents and the fry newly hatched brine shrimp and finely ground flakes. The fry grew quickly and were able to reproduce at the age of 4-5 months.

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