How do I use these?!

Hey so my boyfriend got a Hydroponics kit last year from Goodwill. And the kit came with a bag of these style sponges as well as the default conical Style sponges. These don't fit in the conical style frames the way that they should. Especially if I roll them up like a burrito to try and contain the seeds the bottom part likes to push out from the frame because of the way that the frame is shaped. And so because of that these don't really work well in the hydroponic system I have.

So my question is that if I were to use these and maybe a different style of Hydroponics kit or in something that could be self-made. Or are these more meant for germinating seeds on a flat surface before placing the sprouted seed in the conical style sponges to then further take root and start growing and such.

Any information on these would be amazing as I have tried to Google search these and all I am getting is information about the conical style sponges or the square sponges. Or any out of the box suggestions would also be welcomed too. Thanks in advance!