I've read posts in here describing that you get organic potting soil, sift or pick out any big chunks, lay in about a 1 1/2 to 2" layer. You wet the soil until not quite covered with water and press it down. Then you cap it with sand or Eco or gravel, etc. about 1 to 1 1/2". Then SLOWLY pour in your water using a bowl or layer of something to break up the flow. Then you do a 80 to 90% WC to get the cloudiest water out then run your filter until it clears completely. Then clean your filter and you're good to go.
All you experienced dirters out there please say if this is correct and do you have additional tips? I am about to change out the substrate in my 29g and it has fish in it. I'll be putting them in a 20g tub with heat and airstone during the change out but would not want to keep them out of the tank for more than 24 hrs. Is it possible to do a dirted tank and get things suitable for the fish in that time? If not, I'll just put in the Eco fine grade by itself. Your help will be greatly appreciated. Thanks, OS.