Absence Of Fry

[Franck]

I have female about 2I/2 inches for going on three months. It appears to have a dark gravid but no babies during this time. Could she be sterile or needs a mate?

 

[Rtessy]

What kind of fish? What is the tank size, temperature, ammonia, nitrite, and nitrate readings, and what are the tank mates?

 

[Franck]

20 gal. 80 F, ammonia readings good, tank mates are F guppy, 1 F Mollies and Pair of Swords.

 

[Momgoose56]

Which species is the fish you are asking about?
What are the numbers you getting for Ammonia, Nitrate, Nitrites?

 

[Rtessy]

20 gal. 80 F, ammonia readings good, tank mates are F guppy, 1 F Mollies and Pair of Swords.

No male? They don't reproduce asexually, and they're not hemaphrodites, so they have to mate before dropping fry. They can store some sperm, but not for that many drops.

 

[Franck]

Normally, how many drops do they have?

Which species is the fish you are asking about? Guppy
What are the numbers you getting for Ammonia, Nitrate, Nitrites?

Tetra Tabs are in the OK range

 

[Momgoose56]

If they have ever been impregnated they can drop 1 to 6 times over 6 months. Sperm is only viable for about that amount of time. Got a picture of her you can post?

 

[emeraldking]

If they have ever been impregnated they can drop 1 to 6 times over 6 months. Sperm is only viable for about that amount of time. Got a picture of her you can post?

Not quite correct...
When a male and female mate, doesn't have to mean a pregnancy right away. For such a female is able to store sperm packages. Unless, she allows a sperm package to go further, only than she'll be impregnated. Not earlier...
One mating can establish 1 -7 pregnancies (mostly less). And such a female is able to store sperm packages for over a year. I do have mention that the quality of the sperm packages will become less after such a while. But I have had healthy offspring of the 6th and 7th batch. I also have to mention that when it comes to the 6th or 7th batch after the original mating, the number of fry is lower.

 

[Franck]

Good information. Thanks

 

[Momgoose56]

So, the science and speculation is out there and agrees that guppies can store sperm for a 'long time' The 'agreed' amount and range of time is variable, averaging between 2 to 12 months, depending on guppies studied (wild vs. captive), anecdotal observations etc. But official studies of stored guppy sperm agree that quality and viability of that sperm deteriorates over time.
If you've had the female guppy, for three months, and she hasn't produced offspring in a tank where there are very few guppys and no males, I'd guess that either: that female guppy is not holding sperm, tank conditions aren't optimal for her to produce fry, or the sperm she's holding is not viable (not able to fertilize eggs that will result in viable offspring).

How long can guppies store sperm?

 

[Guanchy]

20 gal. 80 F, ammonia readings good, tank mates are F guppy, 1 F Mollies and Pair of Swords.

if she has not had any contact with a male she would not be pregnant, a gravid or dark spot doesn't always mean she is pregnant

 

[Franck]

Thanks all for your responses. Another question: assume she is going through her stored eggs, if she mates at that time, will the new sperm block the old eggs and start a new flow of different fry?
Franck