Picus Catfish

Welcome to AC:)

How fast they grow is a sort of unanswerable question because it is reliant on so many different factors (and not all fish are the same size).

As for how large of a tank, one adult should have no less than a 29g tank. The bigger the better.
 
I believe there are different varieties of Pictus as well. I believe those with horizontal lines across the body can get over 8" while the spotted variety get around 5". I am not totally sure about that but I think I have read it before. I have the spotted type and they seems to have slowed growing after hitting the 4" mark.
 
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