I was also puzzled by the same question whether there is any difference between normal and jumbo cardinals when I wanted to get 100 cardinals for my 4ft a few years back.
For a start, you may try Gan's Aquarium as Mr Gan has lots of experience in cardinal. He has been importing cardinals for many years. According to him, the difference depends on where the cardinals were caught- Brazil or Columbia. I can't remember which location is jumbo size cardinals from but his aquarium will always have two types for you to consider. I got the jumbo size and pay slightly more for them. But certainly not double priced the smaller ones.
Frankly speaking, I really don't know whether they are normal size grow bigger or Jumbo gene? But they are quite stable in my tank for 2 years.
At times, Colourful aquarium has bags of very big cardinals at very good price. To me, they are jumbo!
Last edited by Justikanz; 5th Dec 2006 at 22:24.
Reason: Removing immediate quotation
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