I built one of these. Unfortunately the screen material clogged while I was at work, and the eggs died.

I am going to build another one with two modifications. First it is going to be built onto a short sponge filter. This should make it clog resistant. I am also considering adding a second piece of screen at the top of to keep the eggs from washing out. That would trap the fry though. A better approach might be a V shape, so that the eggs cycle through areas of high and low flow. This may more closely match the swirling effect observed in the female's mouth.

Related: I found a University extension paper that described using empty inverted 3-liter bottles as an impromptu McPherson jar for hatching catfish eggs. One advantage to this approach is using a powerhead instead of an airlift. In my case I have extra water flow, but a shortage of air ports.

-ellie