Platy Lifespan

Question
Hello.  How long does a platy live?  I have a female that I've had for about a year and a half.  She doesn't seem too active anymore and looks a little pale in color.  She usually hides behind decorations most of the day but always comes out to eat.  I can't see any signs of disease or illness.  I was wondering if she is just old?  I have 11 other platies in the tank that are fine.  It's a 35 gallon tank and I keep it well maintained with a 35% water change every 4-5 days.  No ammonia or nitrites, and nitrates are kept below 5 ppm.  Ph level stays at 7.1.  Over the last few months she has become more and more reclusive.  She did give birth to fry about 3 weeks ago, but that's the 5th time she's given birth, that I know of, since I've had her.  There are 2 males and 10 females in the tank, so she isn't harassed.  Just wondering if you have any thoughts or if you've seen this in your experience.  Thanks for taking the time to read this.  Hope to hear from you soon.  Have a great day.

Answer
Hi Mark,
It seems that platies can live from 3-5 years. It depends on the water conditions and probably genetics. I would think that your platies, especially since you give them such good care, would live several years.
It could be that the platy that is hiding is a little stressed from all the babies she has given birth to. You could try feeding her more vegetable type foods.  There are vegetable type flakes, sliced cucumber or even  algae wafers. Sometimes more vegetable foods increases their color and health. Since you don't see any visible signs of disease just keep an eye on her and try feeding her more of the vegetable type foods and see it you notice any change in her color and behavior. Also, does she have enough hiding places to feel secure? Sometimes fish will act sick if they are feeling a little stressed and don't feel they have enough hiding places such as plants or even cave-like structures.
Hope this helps,
Karen