If you want knowledge about Oxalic acid and varroa, the article below will enlighten you.
Journal of Apicultural Research: volume 54, Issue 2, 2015
Towards integrated control of Varroa: 2) comparing application methods and doses of Oxalic acid on the mortality of phoretic Varroa destructor mites and their honey bee hosts.
The above is an 20 plus page research article studying Oxalic acid pertaining to Varroa over an 18 month period. The single best study I have experienced. These researchers thought of every conceivable detail, down to figuring out to account for natural honeybee death and building a trap to compensate for natural death so as to account precise results. Simply stated, THE BEST ARTICLE my eyes have experienced, so detailed, so through.
I am not saying treat your bees, that is your decision. I am saying here is info if you please.
Cheers
Van