In a 6’by4′ plastic pond, is it possible to prevent mosquitos breeding by putting in a few drops of bleach daily?
Or is that Summit Dunks, (B. th) I think they are called on line- more expensive though- and meant to suit 100 sq ft
b) available in a store? I have tried Home Hardware and Can Tire and Home Depot with no luck.
Bleach will only kill bacteria, not mosquito larvae. The active ingredient in Summit Dunks is Bti (Bacillus thuringiensis israeliensis), which is toxic only to mosquito larvae and will not harm people or pets. The product you mention (in the puck or donut form) is available only in the U.S. and hasn’t been okayed for use in Canada. Bti is available here under the brand name AquaBac, which does seem to be available at Home Hardware. For a small pond, simply use less.
This info on mosquito control from the Ontario Ministry of Agriculture and Rural Affairs (OMAFRA) tells you more about Bti.
Remember that mosquitoes can still breed in places like large puddles, birdbaths, plant saucers and other small water collection areas. Dump these out and/or replace the water periodically. Mosquitoes also don’t like moving water, so adding a bubbler or small fountain to your pond can make it less attractive for breeding.
And Bti is effective only on the larvae, so will reduce, not eliminate mosquitoes in your yard.
I hope this is helpful. Enjoy your summer.