Re: Mystery Fry

[IDMiamiBob <IDMiamiBob@aol.com>]

Leo writes:

<< now the mystery..
 
> This morning I noticed something very tiny swiming in the fry tank at the
> surface. Fearing something bad I had a closer look with a magnifying glass
> ( these old eyes you know ). What I saw was several tiny fish -about 8--
> that looked even smaller then the borelli fry were when they became free
> swimming. I immediately called my wife to look and she said that they
> looked like the borelli did when they were " new ". They don't have a yolk
> sack and are very active but stay near the surface.Since the small borelli
> stay near the lower half of the tank they have not eaten these mystery fry
> yet. I put in some liquid fry food to give them a chance to grow.
 
> Has anyone on the list any ideas where these could have come from?

Probably killifish, if indeed they are fish.  WHere they came from is hard for
me to say.  You'll have to trace back everything that has been introduced into
the tank, particularly plants.  Eggs of some "annual" killies lay dormant for
up to six months.  Others which have shorter gestations will easily survive
transporting with plants.  Have you introduced peat into the tank? Did you
boil it first?  If not, it could have contained eggs.

> Could some of the eggs from the original spawning have remained dormant for
> 11 weeks ?

No, very VERY unlikely, but from this distance, I won't rule out anything.

> Could some other dormant fish eggs been mixed in with the brine shrimp
> eggs?


Again, killies, but I doubt very strongly they awould have survived the salt
thing.  But then again, many American pupfish, which are killies are extremely
comfortable in saline environments, as are some Fundulus.  I've collected F.
heteroclitus along the edges of Chesapeake Bay.

> And most ridiculous of all, could 11 or 12 week old borelli lay eggs?
  >>
If this were the case, they would have sexed out and coloredup.  In twelve
weeks, not likely.  In any case, I would separate the mystery fish, and go
back to feeding the interlopers microworms, and some kind of infusoria if you
have it.  My experience with liqui-fry is that it is better suited to feeding
daphnia and other filter feeders.  I would expect it to foul your water before
it did any good.

If you can save them, I would like to know what they become.

Bob Dixon