Size of tank in gallons or litries.
How many fish and which type.
Water stats in ammonia, nitrite, nitrate, and ph.
Being skinny can be old age, fish tb, internal parasites.
have the fish lost weight due to not feeding enough.
Signs of internal parasites are.
Long stringy white poo, or clear mucas poo.
Being skinny or bloated.
Sunken in belly.
Enlarged anus or red inflamed anus.
Bent spines sometimes.
Sometimes the fish will swim on its side.
Depends on which parasite it is as not all internal med work on certain parasites.
With worms you usally treat to kill the adults then retreat again to kill any young that are left.
Not sure on meds in australia contact colin t a member of this site.
[URL="http
/www.fishforums.net/index.php?showuser=38786"]http
/www.fishforums.net/index.php?showuser=38786[/URL]