I am so sorry it took so long to reply, I got "whirlwinded" by life. Hopefully you've gotten to try it out. In any case, my dog's weight is about 50 lbs. I don't think any exact amount is critical, 1Tbs or even a couple or a few Tbs of tomatoe juice. My dog just loves it so I just dump a little in her bowl. (Beagles eat anything). Time of day dosn't seem to matter as I basically do it whenever I remember each day, again timing is not apparantly critical. Good luck :)