Can plecostomus and corydoras coexist together?

they can coexist just fine, as long as your have enough bottom area to allow all of them to have their own spaces.
 
Should do fine if you have a tank with ample floor space for all of them. Rhino plecs tend to be fairly docile as they grow up, but a little more territorial about their favorite spots. Mine brushes clown loaches out of his spot, but does'nt damage anyone. When he's out of his spot, he's quite social and I've found him with a ringlet pleco, or clown loaches actually sitting on top of him.
 
yea i noticed that about the little territory they prefer the stay around but mine usually doesnt chase my other fish away unless theres food..... so looks like its a go ahead on the cories?
 
i have a pleco and 2 cory cats I had them in a 10 gallon tank for over a year and now in a 29 gallon tank..they have been fine together. I had just the 3 and I finally added a few other fish with them in the 29 gallon tank.
 
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