Feeding Goldfish and Constipationi

Question
Hi David,

I have 2 goldfish in a 40 gallon aquarium.  I do weekly water changes of about 25% and I vacuum the gravel.  Water parameters are Ammonia/Nitrite are zero, Nitrate is between 0ppm and 5ppm.  Water temp is 21 degrees.

I need some advice on feeding my goldfish.  One is fine and has no problems at all with feeding and when he poops it is short and thick.  The other goldfish is a different story.  He eats the same amount but when he poops, it is trailing after him and is very long.  Most times it has air bubbles in it too.  

I need to sort this problem out as I have been told to not feed the goldfish for 3 days and then feed him peas only but when I do this the same thing happens - trailing poop.  His stomach at times looks slightly rounded and I can't help but wonder if he is in pain.

I feed my goldfish every day and I feed them a sprinkle of flakes.  About twice a week I feed them peas - about a pea and a half each - I cook them from frozen, let them cool down and then de-shell them and squash them before putting into the aquarium.  Can you give me some good feeding guidelines and some tips on how to eliminate constipation


Answer
Hi Katie:  Trailing poop is a sign and symptom of intestinal parasite or worms.  Continue to feed them as you have been that is a good diet for them both... but you will need to get some medication at the local aquarium  that you can add to food... and that is specifically for parasites or worms.  They have medicinal gels that you can add to pellets that work good... keep me posted... dave