ok i have 5 neon tetras in my tank and i just want to ask do there stomachs change shape??? Ive been sitting here looking at one for the last 5mins and its stomach becomes really big shrinks back slighly and becomes big again... any ideas???

Did you feed them recently? What kind of food? How much?

My piggy black neon girl ate a huge (well huge for her size) crumble of algea wafer once and her stomach did the same thing. It was swelling and going back to normal and moving around like there was an alien inside, but she looked a little pained. I didn't feed her for 24 hours and then fed sparingly after that (and no more algea wafers) and she was fine.

the fish might also have some type of disease so you might want to check that as well! Hope i was some help but i am not too good with fish and i am sure someone else can tell you better!
Thanks!

that's interesting, i woudn't have thought of that at all kissy. so not feeding it for a day or so helped it along w/ it's full stomach? at the alien rummaging around the belly of your little neon.

hope that's all it is for your little guy, star. keep us posted.

hey dean, what disease do you think it might be?

Yah I really have no clue what was happening in her tummy but my best guess was that her stomach was trying hard to break it down and digest it. I believe it happened again when I accidently fed too many freeze-dried bloodworms and she ate her share along with Rummert's share. I fasted for 24 and then fed lightly and she was fine again.

Its only the one neon thats having the problem so i will stop feeding them for 24hours and keep you posted...Kissy you explained it well it is like a little alien moving about in the tummy. EWWW making me feel sick lol

Tell me how it goes

i left it for 24hours they seem fine now thanks guys

I'm glad it just turned out to be overfeeding. It sounds like that neon was the dominant food pig, so if you are not already, try spreading flakes all over the surface and feed smaller amounts more frequently