Aquaponics spawning yellow bullhead catfish

bullhead

Three years after implementing a very thoughtful and ecologically systematic aquaponics design, sheer utter neglect has resulted in our first yellow bullhead catfish spawning!

Our motivation for trying this fish species came after learning the most likely candidate food fish to spawn in a closed aquatic system that is temperate (80 degrees summer / 40 degrees winter), is the yellow bullhead catfish (Ameiurus natalis), courtesy of the New Alchemy Institute:

“Tests were carried out using both tilapia and yellow bullhead catfish in the hydroponic solar pond system. Catfish can tolerate much lower temperatures than tilapia, and, young catfish can be obtained more easily than young tilapia.”
Male bullhead catfish protect the egg mass after spawning (fish and egg mass with bucket nest in picture above), so it is very possible that a week from now we will be observing our first baby catfish!
Our plan will be to install a small diameter wire cage in the tank downstream of the catfish tank. That way when the baby fish are active at night, coming to the surface to feed, they will flow through the pipe downstream, collecting themselves without us having to disrupt the nest and stress the fish.
Another thing to mention is that I wonder what it was exactly that encouraged the fish to spawn… besides spring being this species natural time to spawn, I am considering the fact that comet goldfish (Carassius carassius x wakin) spawn in the same tank, and they have spawned continuously for the last month (could it be the goldfish spawning hormones that gave the green light?).
We’ll see how this new fish adventure unfolds and we’ll let you know how it goes!
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6 thoughts on “Aquaponics spawning yellow bullhead catfish

  1. Jonathon,
    Am intrigued by your YBH Cat success re:spawning.
    Coincidentally, I have both feeder gold fish and rosey red (FH) minnows in my YBH catfish tanks
    (livestock water troughs); but despite the bullheads being 4 years old and 13 to 14 oz size…..I’ve yet to have any ‘accidental’ spawning.

    Using river/rock gravel media in a very dark setting (coupled with black plastic hiding boxes),
    the fish have shown good hardiness (disease and temp), but only slow growth an no reproduction.
    Have about 12 fish in 2 separate tanks. They are fed trout chow floating pellets, some night crawlers and the forage fish they catch.

    I use 1 aerator per tank and change 15% of water weekly in a 40 gallon setup.

    Any suggestions for improving growth, reproduction would be extremely appreciated.

    Bob in Washington

    • There are lots of details I could note, the most important is that 1/3 of the fish lived longer then I expected, 5 years… Yet never successfully reproduced, although they did lay eggs at one point and it may be that there wasn’t a male available to fertilize the eggs. My assessment is with better conditions (more oxygen and food) they would have thrived and reproduced. With that said, they don’t grow very fast (due to the cold 6 month long winter, there is no growth) it takes two years or more for the fish to get to edible size. We eat the last remaining catfish (one fish), and mirror carp 3 years after adding to the tanks.

    • Other thoughts to consider from our experiment… How closely does your setup mimic spring like conditions? It is my understanding that the fish need to think it is spring to induce spawning (system needs gradual warm up, not immediate summer like conditions). Also, the 5 gallon upright bucket that the eggs were laid in had two inches of course sand in the bottom, I don’t know if that was important. Lastly we had a diverse natural food chain in the system, snails, yellow clams, crayfish at one point, plankton, baby goldfish, who knows what else! I’m sure that a diverse food source is important as well… egg laying uses a lot of protein and fat. Hope this helps!

      • A few other points… We never did a purposeful water change, but we did have 55 gallons of aquaponics beds the water ran through, and in that we put red wiggler worms. I know that both tannins and hormones can help to induce spawning. Tannins (or plant humic acids) have been shown to reduce stress in fish and encourage reproduction https://tanninaquatics.com/blogs/the-tint-1/humic-substances-in-freshwater-aquariums

        In fact, as I am looking at the picture posted in the original blog post, you can see the tented water, which most likely is showing a high amount tannins in the water at spawning.

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