I'm glad to see things are working out for you with the vodka. I know you and I talked about the vodka before with my other tank and I ended up taking the Vit C. route instead. Our tanks are very similar (see the sig). After starting the VC it made a huge difference within a week. Water clarity was the first thing I noticed and changes to my zoa garden happened very dramatically. Almost, all my zoa's started "brightening" up. My SPS started to do the same. I am following pufferpunk's personalized recommendations for my water volume and took a 3rd off the required amount. I dose 4 drops of MB7 twice weekly. 2 drops of AA's weekly, I also run carbon and, GFO in a BRS reactor.
Our bio load is pretty similar as well, 2 clowns, 2 blue/green chromis, Yellow watchman, 6 line wrass, CUC etc etc. I feed rods original daily. once a week I add reef roids and reef chili to the rods and turn off the power heads and feed like normal. I like to broadcast feed my coral vs. spot feeding. No need to blast them with food, I'm sure they will get plenty from the water column to begin with. I'm also surprised you get 0 P04 with feeding flake. That was the first problem I ran into and completely stopped feeding flake and pellets all together.
Enough about me and lets talk about the coral. I have one particular coral that I have had for nearly a year. it's a pink stylo that started out as 1/8th inch frag (seriously) got a little growth in the beginning and then it browned out. After starting VC and mb7 within 3 weeks color started coming back, 2 weeks after that I noticed new growth, something I hadn't seen on this coral in some time. Now after continuing the VC regimen for about 4-5 months I believe it was the right choice.
Also, my other hobby is photography, so if you want some pics and you don't live very far away, I can take some better pics if you need.