Hey, if you guys were referring to my picture, it's easy to divide them like this.
Just get two bamboo plants (or cut one in half like I did) and envelop a suitable net around the bamboo stem. I tied the net on one of them, and for the other, I had some extra net length so I just wrapped it around it a few times. My tank has two half inch glasses on both sides of the center of the tank in which a glass can be inserted (for completely dividing two sides). I tied my bamboo to the aquarium on top and at the bottom I just firmly stuck it into the gravel. Just make sure that there is no space between the bamboo and the tank glass. They try to go through the net (my male poked his nose through one whole at a time as if he would find a whole big enough to get through) After they realize that there ARE NOT any spaces through which they would go through, they will start trying and occasionally meet at the net to communicate, flare etc.
And yeah, the neon tetras would show up randomly on each side, most times all together so they use the full tank size.
P.S. Don't forget to thread a thin stick through the top of the net to keep it secure.
I'm sure you didn't have to throw out your tank because it was snail invested. Just take out the decor, toss the substrate and remove what snails are still lingering in the empty tank.
Even just setting it outside for a day(empty) will get rid of your snails.
I know I probably didn't need to get rid of everything but the fact that the water was all green and then I had nematodes, I just wouldn't be able to relax if I didn't get all new stuff. I was so disgusted by it that I didn't want to keep anything.
I didn't like pond snails, now I don't mind having them. My fish are starting to eat them, so I'm always sucking shells out of the gravel during water changes. I must say, I prefer MTS and ramshorns over pond snails.