yamaonna

Anyways about a month and a half ago I noticed a small lump on his right lower side just before the anal fin. It hasn’t changed but It does look like some scales are raised slightly in that area. I have tried to find an accurate internal betta anatomy picture but to no avail.
<This one is about right:  http://www.bubblenest.net/betta_anatomy2.jpg >
I know the swimbladder is along the back of the fish and all his internal organs are in the area between head and anal fin. But how far forward are they…where is his stomach, anus and intestines?
<Take a look at that image – it’s pretty good.>
Thinking it might be constipation I fasted him for one day and substituted Epsom salt for the aquarium salt (1/8 tsp per 5 gallons).
<Doesn’t sound like constipation.>
I never actually see him potty but I did see him the second day on the Epsom. Do fish potty quickly, or does it hang on for a while?
<Mm, depends on the food.  To be honest, I never see my betta in the act, either.>
The color was a light brown.
<Normal.>