Dying of old age?

I've got two fish who seem to be ill, there are no problems with the water parameters and they are still eating. But age is against them, they're both 3 years old. One is a platy who has taken to sitting on the bottom of the tank, sometimes on his side, rapid gill movements, he can still swim and eat. The other is a sword tail, similar to the platy he doesn't swim a lot and is usually resting in the roots of a planted rock.

So my question to the forum is are they passing from age related issues? Or am I missing a clue to something I can help!

Please help!

 

Well if you had your tank running for 3 years, I would probably say that 3 years is getting old for a platy - their life expectancy is around 2-4 years. Has this been a sudden change or gradually over time?

You might want to check your water parameters just to be sure though... Sometimes after a few years, your tank may start to show some symptoms of "old tank syndrome"

 

Gradually over the last week or so, he's been much less active than the others. Parameters still test exactly the same as they did prior to their behaviour change, all completely healthy.
Old tank syndrome? Could you tell me more please.

 

First, can you tell me HOW you are testing your water parameters ( liquid test kit? ) and the exact numbers? ie: ammonia/nitrite/nitrate, etc
Have you noticed any changes in your PH ( usually a sign of OTS )

Here is an article on OTS - might be better at explaining it: