Dawn from Sarasota, Fl writes,
Drain Flies: 40 ft long lanai drain
Any suggestions on how to use DF5000 on a drain that runs the length of our entire lanai (~40 feet)? And the covers do not come off, so we can't clean any traps (if there even are traps on lanai drains) that may be underneath. We've tried pressure washing into the drains, digging a bigger trench where it drains outside (to eliminate standing water); using a different (but obviously less strong enzyme), using gel bleach, using vinegar & baking soda. We still have the flies, and tonite after using the vinegar/baking soda again, hundreds of larvae came up out of the drains... yuck!
We have never really had this question and we are not exactly sure. But our best suggestion would be to foam the drains with invade bio foam. It is a microbial foam, like DF 5000 but in a foam, and is great at getting in all nooks and crannies where drain flies breed. This would be our best recommendation.
Answer last updated on: 05/15/2012