pregnant tetra?

Question
i have a 10 gal. tank and it has been up for about 9 months. the pH, ammonia, and nitrite levels are all normal, however, in the past, we did have some problems with the nitrate levels. they were very high. i have three zebra tetras(i believe that is what they are called), 2 neon tetras, one bleeding heart tetra,another type of tetra that i am unsure of the name, but it has sparkly, one-colored scales, and one that eats the algae on the bottom that i am also unsure of the name. i am not sure of the gender of any of these fish. i believe that one of my neon tetras is pregnant. it is eating fine, but i am still worried that it may be sick instead of pregnant. my first question is, how do you tell if your neon tetra is a boy or a girl? also, if my tetra is a girl, how can you tell if it is pregnant? if it is not pregnant, what other solutions to her sudden weight gain could there be?

thanks,
Sarah

Answer
Hi Sarah;

Egglaying fish don't really get "pregnant" so to speak. They get full of eggs that must be fertilized by a male as they are laid when they spawn. If they can't or don't spawn the eggs are re-absobed into the body.

Sometimes it's hard to tell if it is eggs or sickness of some kind. Look at the scales and see if they stick out kind of like a pinecone. Or, if the fish seems to hide more often or breathes faster than normal. This would indicate a condition called "dropsy". It isn't a disease itself, but a symptom of disease. Because there are so many possible causes it's hard to treat. Here is a link to info on it;

http://badmanstropicalfish.com/articles/article24.html

Let me know what you think and we can go from there.....

At Your Service;
Chris Robbins