Your ammonia should be 0. Either you over feeding them or your filter is not
working.
6 gold fish if they big, seems too much in a 29 gal.
KH 120-180 ppm is ideal, if you talking about 10-11 ppm that's too low, you
can have PH swings. Add buffer.
Your gold fish, blotted, protruding scale, means DROPSY! There is medication
for that at any pets store.
Get your water into the correct numbers and add medication to the tank,
don't feed them for a few days. Find out why you have ammonia, is you filter
working right, have you changed it, throwing out the good bacteria?

JS

"weetat" wrote in message
oups.com...
Hi all ,

I have 29 gallon tank using mechanical top filter.
My pH is 6.5 to 7.0 and KH is 10 to 11 .
Ammonia is 5 mg/l

One of my goldfish is bloated . I have done 50% water changes and
added the Jungle Fish Intensise Medicine and some crsytal salt into the
tank.

However , the gold fish is still bloated and his body scales is
protruding.

Anybody have ideas and suggestions how to solve the problems.

Thanks.