SILVER DOLLAR SICK OR PREGNANT?

Question
I have a 250 litre Juwel bowfront community tank which I keep at 84 degrees.
Ph is just below 7. I feed my fish a diet of flake, frozen and occasional live
daphnia and bloodworm in the morning just after switching the lights on and
at night approximately half an hour before switching the lights off.

I currently have various Corydoras, including breeding Pandas, half a dozen
Marbled Hatchets,  some Cardinal Tetras and Harlequins. The larger
inhabitants currently are two 6" Synodontis Eupterus, four 2" Firemouth
Cichlids and six 6" Silver Dollars.

I've just noticed that one of the Silver Dollars has got VERY big in the body.
It's eyes seem to be popping out  and there is a lot of mouth movement, as if
it's fighting for breath. It doesn't seem to have the redness in the fins of most
of my other Silver Dollars and looks very pale in the body but this may be due
to it's size. Do you think I have  a pregnant female or just a sick fish? What
would you recommend?

Thanks,

John

Answer
Hi John:  sounds like she is sick...pregnancy doesn't often involve eye bulging.  There is a disease called dropsy which is caused by internal parasites and/or an intestinal blockage... the result is the fish balloons up and in normal fish like a platy they begin to look like a pinecone... I would imagine that in a silver dollar and other compressed fish like angelfish that they would look similar to what you have described to me.  If the fish is still eating try to feed her brine shrimp/frozen peas (thawed of course) and see if she will poop.  Look up on google images for dropsy and see if that is what she looks like... You can treat her with some antibiotic for parasites... based given in her food... but dropsy does not have a very good outcome... look at the pictures on the net and then get back to me about your opinion of dropsy... and in the meantime I will try to do some research on silver dollars and dropsy... dave