Theories

Based on the developers' experiment data, the mosquitoes will be attracted by carbon dioxide (CO2) and are used to fly along to the wall. If it flies into the trap, it can not fly out because the exit is at the center.

Materials

Carefully cut the PET bottle along to the top edge of the label, which should be the most prominent place. You can get a funnel-shaped piece and a cylindrical piece.
Mix sugar and water, the ratio of the volume is 1 : 4. Pour the sugar water to the cylindrical piece and add some yeast.
Invert the funnel-shaped piece and place it inside the cylindrical piece.

Based on the developers' experiment data, transparent : green : brown = 766 : 434 : 470, transparent bottle gets the best result.

Based on the developers' experiment data, no seal : seal with hot melt = 835 : 384, no seal gets better result and it's easier to wash. If you didn't cut the bottle well and you are afraid that the funnel-shaped piece would not hold on the position, using stapler would be a better choice rather than tape.

Based on the developers' experiment data, funnel-shaped piece : funnel = 1427 : 120, funnel-shaped piece gets better result. The developers guess the reason is that the entrance is too small to let the mosquitoes fly in. In my video, the mosquitoes even use their bodies to build a wall to prevent their partners from the trap. I don't know how they done it.

Based on the developers' experiment data, Wrap with black paper : no wrap = 835 : 766, not much difference. I feel that it's doesn't matter after my experience too.

I don't know if yeast means the only one thing in English, but it's really easy to buy wrong in Taiwan because there is a lot of stuff that can be used to bake bread, like baking powder and baking soda. If you are using yeast, it will convert sugar to alcohols and carbon dioxide (CO2) and your trap will create bubbles and smell like wine after a while. Because the developers didn't test if the smell is related to the trap or not, i think it's better to follow the original guide. The yeast could be found in the shop for baking supplies. If you told the clerk that you want to use it to catch mosquitoes and it will smell like wine, you should not buy wrong.

The news said that different yeasts may come to different results with different genera of mosquitoes. I don't know if it's truth or not. The developers use the yeast that is used on steamed bread and i use the yeast the is used on bread.

I use black sugar instead of granulated sugar and the result is still very good.

Somebody made the same trap and put it at the same place as mine. The difference is that he uses 6000 ml PET bottle instead of 2000 ml. Although some mosquitoes dies in it, the mosquito density is just the same in the three months. I don't know if it's because that he buy the wrong yeast or the exit of the trap is too big so the mosquitoes can easily fly out. If uses smaller bottle to make the trap, because the exit is closer to the wall, maybe the mosquitoes would easily fly out. It needs more experiences to prove it.

You have to let the mosquitoes have no spaces to land at bottom and there's still enough spaces to let the mosquitoes fly into it.

Although the developers have changed the mix unit from weight to volume, it's still too complicated to a lazy person like me. As my steps, i make the bottle first, add some sugar (not much, or the yeast cells will die. I put less than the guide.), add some yeast, add water and shake the bottle, then it's done. The result is still good.

game writer guySeptember 27, 2020 at 4:45 PM
Good stuff. I found a really helpful scholarly article which details the most efficient blend of sugar and yeast: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2984570/#!po=0.409836
By my calculations the ideal is 1.5 tsp yeast, .5 cup sugar, and .5 liter water. Try it out!
D. ChangSeptember 27, 2020 at 4:46 PM
They also say it's much more effective to add a stinky sock near the bottle to aid in attraction. My sweat is not very stinky so I have struggled with this part !