The newcomer asked the fish tank for insects What insects are there for fish？

　　The newcomer asked the fish tank for insects What insects are there for fish？What kind of insect is shown in the picture, found in the filter material, please help

========How did the fish friends of the Xianglong Aquatic Alliance comment==
STDkmZJS Yuyou said: mosquitoes, raise a few swallows, there will be no more in a few days
Hawkins Luzhou Laojiao Yuyou said: it hurt the dragon instead
Hawkins Luzhou Laojiao Yuyou said: any disinfection potion has little effect on such a large body of water
Hawkins Luzhou Laojiao Yuyou said: Boil it in hot water.
Wanyi Wanyi Wanyi Yuyou said: Not a red worm, the egg worms under the water mosquito will change from red to black without affecting the water but it is disgusting. Your fish tank is not well sealed so I ran in and laid eggs
E-day E-point Yuyou said: Take out the filter material and wash it, just boil it with boiling water.
E day E point Yuyou said: Red worm
Long Yun Tea Fragrance 2 Isnt this red insect?How to quickly open the arowana*Newly bought silver arowana opening a few days/How long does the new fish enter the tank)It "s good to keep arowana at home~Who is suitable for arowana?Which arowana is suitable for small tank breeding!What is the best filter for arowana#The meaning of raising arowana at home" Solola Fish，