Water Butt insects?

Antispam

I would empty them out and clean with pressure washer or disinfectant the cheap value stuff or Jeyes fluid. I always do mine at least once a year and always keep a lid if not already done so on them

Gorgeous_But_Grumpy

I once heard that rubbing tumble dryer sheets over your skin prevents bites. Since doing it I have never been bitten again, despite the fact I was a magnet for them in the past. Cheap and makes you smell nice
I also use them as an anti-static for dust on tv screens.