Why does my catfish spit gravel out of the tank?

Samaka

Jack Dempsey
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Sep 6, 2013
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I have an 12" e-cat in a 125 gal tank. I've had her for 4 years. Started out as a 2-inch fish in a 10 gal, then moved to a 55 as she grew, and is now in the 125. There usually is a line of dried gravel stuck to the plexi-glass sides above the water line. She also sometimes spits gravel out of the tank near the openings where the filters hang (she has done this is each of the 3 tanks that I've kept her in, ever since she was 2". I have about 5 inches of gravel, she has a clay pipe that is a bit longer than she is and about twice as wide as her girth.

Why does she scoop gravel, swim to the water surface, and then spit it out of the water? Is this normal catfish behavior? Or is this female behavior (I think this is a female)? Do cats do this if there isn't enough space? Does anyone know? Thanks
 

thebiggerthebetter

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Mine did the same and I've read of other examples. So atm I think it is normal. It always seems to involve small gravel. They aim to spit it out of the tank. As for the underlying reason, I'm curios as well. Maybe they like their native substrate more - mud? IDK if they occur in the wild over gravel.
 

Samaka

Jack Dempsey
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Sep 6, 2013
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Interesting idea! Glad you knew what I meant, as they aren't just rearranging stuff like cichlids but aiming to spit gravel out of the tank. Btw, I wonder if other types of catfish have also been seen doing the same thing?
 

thebiggerthebetter

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I cannot remember atm. But yes, they aim to get rid of it. If there a hole or a crack or an open top, the gravel will be on the floor.
 

thebiggerthebetter

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Actually, I thought about it and remembered another possible explanation. Mine spit the gravel over a bunch of upright-standing plastic plants in what can be interpreted as an attempt to weigh them down to the bottom to create a more secure, more shady hiding spot as I have not provided mine with a good spot so I could see it. The catfish succeeded in achieving this goal.

Still, I recall finding gravel on the floor and also others reporting the same thing. Could be a by-product of the same technique. IDK yet which of these two hypotheses is viable - need more experimenting to distinguish.
 

Samaka

Jack Dempsey
MFK Member
Sep 6, 2013
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USA
Yes, they hate the bright lights that's for sure, but they are needed for the live plants though. It's a give n take situation, but come nighttime, it's party time in her tank! Your hypotheses at least get the gears turning, so when another answer presents itself in the future, we'll be more ready to notice it.
 
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