jack dempseys dying?!

Question
QUESTION: We had 2 jack dempseys one male 1 female...the male passed on a couple of weeks ago for no apparent reason he got VERY dark in color and really lothargic wouldn't eat..laid on the bottom of the tank one minute and the next he was gone. Now, thwe female is doing the same thing only she has these white balls on her underbelly and is jerking as if in shock i cannot find any answers online hopefully you can help me id love to save her. thank you sooo much

ANSWER: Hi Alycia
Do you know what the water quality-ammonia, nitrite, and nitrate readings are/were?

How long have you had the Jack Dempseys?

Have you recently added anything new to the tank(fish, plants, rocks)?

Along with the "white balls" on her belly, did you notice any white stringy stuff hanging off of either fish?  Or excess slime coat?

Christy

---------- FOLLOW-UP ----------

QUESTION: thank you for answering. we haven't checked the water quality but that can be done. the fish are about 8 years old. we have not added anything new to the tank. when the male passed we did clean the tank but we always use the same pieces in it we were told to at an aquarium store. i do not notice any white stringy on her at all and he passed about a month ago, we thought of age but now i am not so sure


Answer
Hi Alycia
Just did a quick check, and their life span is about 10-15 years on average.  And with the second one acting sick, that tells me it's most likely something other then old age that's affecting them.  

I would say check the water quality.  Whenever anything appears wrong in a tank, the first thing to do is check the water quality.  9 times out of 10, that's the source of the problem.  

Is the female acting any better?  
Is she still jerking around?
Still have those little white balls on her belly?
Any other symptoms showing up?

Christy