red wag platy

Question
We just recently started an aquarium with 6 fish (4 zebra danios and 2 sunburst platies).  We have a 46 gallon tank with a heater, keeping the water temp at about 78 degrees.  Everything was going well until today when we added 6 more fish (2 mollies, 2 small tetra and 2 more platies (red wag).  5 of the new fish seem fine, but one of the platies went immediately to the side of the tank and just hovered there for an hour or so.  Now it's hiding under the 'castle' ornament and just now when we fed the fish, the other 11 ate well and this one wouldn't even come out for a morsel.  Do you think it's sick?  Or ready to have babies?  Or just anti-social?  My husband says it's just 'adjusting' to the new surroundings, but the other red wag doesn't seem to have a problem.  Thanks for your help!


Answer
Good morning P.J., thank you for your question.

With my first community tank, I never quarantined new arrivals and lost a few fish that way. I just filled my hospital and quarantine tank with new cichlid fry, so I am not exactly a shining example of an aquarist following perfect quarantine practices. However, you may consider cheaply outfitting a 10 gallon tank with a sponge filter to quarantine new arrivals before adding them to the main tank. One little outbreak of ich and you'll wish you had!

That being said, it does indeed sound like your new red wag is either pregnant or stressed. Hopefully you ended up with three female red wags and one male, a "harem" as they say in aquariumspeak. If you have two males, two females, that should be ok. But if you have only one female and that is the one hiding in the ornament, you may have some trouble. Platies breed constantly - when they are not breeding, they are thinking about breeding! So three males will really harass one female, stressing her out incessantly, which increases the chance that she will abort her pregnancies. Determining the sex of platies is simple - look for the gonopodium in males. You can read further here:

http://www.fishforums.net/index.php?showtopic=46309
http://badmanstropicalfish.com/profiles/profile4.html

Acclimation stress could be another possibility. If no serious water quality issues/differences are present, this usually sorts itself out by the next morning. Watch that all the fish are eating together and that there is no bullying present. Add a tablespoon of aquarium salt (can be found at most any pet store, even the fish dept. of Walmart) per 10 gallons. Your livebearers will love the addition of the salt and no one else in your tank will mind it. Cory cats and plecostomus are two common species that are sensitive to salt, but concentrations no higher than this will not harm them. Good luck with your budding community tank, and feel free to write again. Happy new year!

Nicole