40 breeder?

  • We are currently upgrading MFK. thanks! -neo
A single Rock Bass would fit pretty well. Maybe a few sticklebacks instead if you plan on adding plenty of hiding spots.
 
aggressive doesn't leave you with many options in a 40B. sculpins, sticklebacks, rockbass like dive said, redfin pickerel would all do fine in a 40, but they aren't the meanest of fish.
 
For several years I kept a Blue gill and Yellow Bull Head catfish in a 40 Breeder. I tried other local fish like a black Crappie and a Small mouth bass but the Bluegill beat up both of them with no mercy.
 
A 40 gallon planted would be a good tank for a species only tank of Orangespotted Sunfish male and female, (which are aggressive in the spring). I would say Dollar Sunfish, or Northern Sunfish, but a 40g is probably too small for more than one of those species of Lepomis. (Dollar sunfish are very territorial).
 
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