As for dosing volka, I think you need to do it daily to keep the bacteria going, every 7 days sounds too far a part to sustain a good colony. Did you use some kind of bacteria additive like Brightwell or prodibio? You need to introduce good bacteria in a new system, these product seems to do a good job at that.
If you don't dose regularly, you're just more likely to cause a bacterial bloom when you do dose, which can lower the oxygen levels while spiking the CO2 levels, causing a tank crash. However, he says he's using a reactor, which may operate differently from simple vodka dosing; I'm not sure as I simply don't know.
Despite misinformation from additive fanatics, bacteria reproduce quickly and it's practically impossible to eliminate the common nitrogen-fixing strains from a tank without deliberate intervention with things like bleach, boiling, or megadoses of several different types of antibiotics. Small populations can reproduce extremely quickly -- remember, their reproduction rate when not limited by wastes or limited food is geometric -- once the conditions in the tank change to favor them.
Think about it. You can put nothing in a tank but artificial live rock, dead sand, and some sorta nitrogen source, and a few weeks later you have sufficient populations of ammonia, nitrate, and nitrite reducing bacteria in your tank to handle a bioload. These suckers float around in the air, they're so common. When you add your first piece of real live rock or few cups of live sand, you get even broader populations of bacteria. Yes, you might get an advantage in cycling time by dosing bacteria at the beginning, but once your tank is established it just strikes me as a waste of money.
