Cleaning my soil w/o plants in it, of fungus gnat larvae..tips?

Ok so I tried putting clones that had fungus gnat larvae on the rockwool cubes into my pots with new soil after soaking the cubes in neem oil hoping I could still get them to grow. After 12 days or so and barely any new growth I decided it was best to pull all the clones and throw them away. So I started all new clones that will be ready in about 10 days to plant in the room. Now im wondering what the best method would be to make sure their are no fungus gnat larvae in the soil in any of the pots by the time I put these new clones in there. No chemicals please, strictly organic. Peroxide solution maybe? Just want to get as many ideas as possible by the end of today and then I will implement the best ones! THANK YOU!

mosquito dips

http://www.amazon.com/Summit-111-5-20-Pack-Mosquito-Dunk/dp/B0002568YA/ref=as_sl_pc_ss_til?tag=growwcom07-20&linkCode=w01&linkId=TU44JOK5BAKLNMSV&creativeASIN=B0002568YA

Increase your air movement a LOT and make sure your plants are swinging and swaying in the breeze.

Put a paper towel or something under your pots to wick up the water that sometimes settles and puddles under the pots. Or elevate the pots so that there are no puddles or constant moisture under the pots.

use LOTs of yellow sticky traps…place them near the bottoms of the pots by the drainage holes.

Water so that you get run-off and then discard the runoff water. Wait until soil dries out completely between waterings.Make sure you use garden pots with plenty of drainage holes so that the water can rush through and pull oxygen through the soil and carry out any eggs.

Keep your grow area surgically clean.

Add sand to top of pots it has worked for me i did about 1.5inches of play sand

tstick said:

mosquito dips

http://www.amazon.com/Summit-111-5-20-Pack-Mosquito-Dunk/dp/B0002568YA/ref=as_sl_pc_ss_til?tag=growwcom07-20&linkCode=w01&linkId=TU44JOK5BAKLNMSV&creativeASIN=B0002568YA

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does the BT in the mosquito dips not harm beneficial microbes in the soil?

Pasteurizing Medium
Potting media mixed by home gardeners should be pasteurized to kill weed seeds, soil-borne insects, and pathogens. Pasteurization destroys most organisms and is done by applying heat until the soil reaches 180oF (82oC) for 30 minutes. When temperatures are raised above 212oF (100oC), most of the soil borne organisms are killed and the soil is considered sterile. Gardeners can pasteurize homemade potting soils using a kitchen oven; however, a long-lasting earthy odor can develop in the oven. To pasteurize soil, preheat the oven to 180oF. Then fill a pan with about 4 inches of moist soil and cover it with aluminum foil. Insert a candy or meat thermometer to monitor temperature and place the pan in the oven. When the thermometer reads 180oF, leave the pan in the oven for 30 minutes longer, then remove it and allow the soil to cool. Seeds can then be sown in the soil, or it can be used as a transplant medium for seedlings.
180f water will do the same trick