VSV is more potent. I recommend cutting back by at least 50% of the normal Vodka dose and increasing by 0.1ml until nutrients drop. At that point, a lower maintenance dose should be used. This is what I have found to work well, but every tank is different you and you may need to adjust accordingly. Slower is always better with a carbon source.

When switching from vodka to VSV – is the same dose maintained?

Waterchanges can also lower oxygen levels and ORP. In both cases the effect is temporary and with a well functioning protein skimmer and if a carbon source is added appropriately it is not a large concern

In regards to Borneman, he is certainly correct. If you look at the studies that Borneman and others cite you will also see some differences that are worth considering… such as were and when the carbon is being utilized by bacteria.

There is also no information that I am aware of that suggest long term use increases this risk. I am also not aware of a single user reporting mortality from bacteria or pathogens.

You have probably read this, but if you or others have not I would suggest taking a look at this series by Ken Feldman and Kelly Maers on Total Organic Carbon in Reef Aquariums: http://www.advancedaquarist.com/2008/8/aafeature3

Eric Borneman also warned at MACNA that the increase in C in the water & bacteria in the water also means more bacteria and possible pathogens are on the coral tissues. Long term use can mean more infections on the corals.

Overall, this is why I only do C dosing for limited periods… to help a tank get through that 6-9 month ‘break in’, or to counter some other ‘bio mistake’. I also only use everclear… pure ethanol doesnt have all the ‘extras’ that many vodkas and gins might.