Thanks, I appreciate your interest and input, and whilst not wishing to cause offence, I don't feel much else can practically be done in the particular situation.
There are types of water life that could eat the mosquito larvae and once they were fast moving enough to avoid your watering can maybe stocking the but with some of these might help. I just took a bucket of water form a slow moving part of a nearby stream/small river and added it to my new built pond and within a very short time it has got lots of water boat men insect, beetles and some water skaters which I think help control your mosquito larvae. Since adding the bucket of natural water life to the pond I have not noticed any particular problem with mosquitoes. Stickleback fish might also help but not sure how to go about catching them . Something floating in the water for the mosquito hunters to shelter in when filling your watering can might help the system work more long term. I think tilapia fish are used in warmer climates for this but they would not survive our winters out doors.
I'm not quite sure what the problem is - mosquitoes breed all over the place so trying to stop them in a water butt is a bit pointless I think. I have a waterbutt the other side of a rose arch where access with a watercan is difficult (I did know in advance!) so I just use a small bit of hosepipe attached to the tap to fill up the watering can. I also have a water butt without a lid to catch rainwater and have tied several layers of insect proof netting over the open top.
Point taken - to some degree. Mossies are known to breed in the smallest amount of stagnant water, and the more I can eliminate the better.
I'm trying to reduce as much as possible the likelihood of them swarming in our small garden, as my wife's health is somewhat compromised by their bites. Yes, insect repellents are used too!
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