Ahem Jason how long have you been keeping fish now young man ?
Why isnt this shubunkin doing a months Quarentine before going in with the two bigger goldfish ?
Quarentine has to be the first most important thing in keeping any fish be they koi or goldfish there is an awful virus in koi called the Koi Herpes Virus which has an 80% kill rate and as such is a notifiable problem the Government of both mine and your country needs to know about via the fisheries and farming departments.
In the goldfish world if you thought they had got away with such an aweful virus think again its called GHV or Goldfish Herpes Virus though less virulent than KHV it still has a kill rate of about 50%
The survivors of both Viruses will carry it so any fish put in with them will catch it, and die, so you either destroy the survivors or keep them seperate from any other fish, meaning you would need two sets of nets, two ponds, two filters etc etc .
Worst case senario I know but its one of the reasons we QT our fish.
A parasite on your newbe fish (one of many different ones) means the other two get it and will need treating so you can see why its such important a thing to do.
You cant stint on it and if you do it's a little like playing Russian Roulette, you can only pull the trigger a set number of times before you blow your brains out.
Well its the very same with any fish you buy.
QT means QT not straight in the pond with other fish that are parasite and disease free my young friend
"Lesson Learned".????
rgrds
Dave