This is the big Vibrant post on R2R with 5000+ comments. You will see a lot of success stories, a few horror stories, and some who saw no change at all. I spend quite a bit of time on it trying to help people. I had huge algae problems with my first reef tank and tried Vibrant. It made things so much worse. The owner of UWC reached out to me and explained why I had the problems I did and walked me through. Within a month the tank looked great. Now I try to help others in the same way. There is so much variety in reef tanks that basic directions don't do the product justice.
I feel people try to use it that way and it can cause troubles. Most of the other bacterial based algae treatments do work this way. Vibrant has some bacteria that directly attack the algae itself. I've seen it on my microscope but haven't been able to film it.
@jason2459 captured and posted a video of the bacteria tearing a chunk of algae off a strand. Fascinating stuff. With the current algae I'm battling I am dosing every 3 days put keeping my NO3 at 20ppm and PO4 at 0.08ppm. Even with elevated nutrients like I have (mixed reef) it's starting to take out this algae.
It's use has led to more than one reef tank being smoked, no doubt about it. I can't stress enough about taking it slow, ramping up, and being very observant just like you should with any product. It's not exactly as dramatic as Chemiclean but it is similar. Chemiclean has a ton of positive reviews but more than a few cases where it has killed almost every living thing in peoples tanks. No one seems to be able to narrow down exactly what the trigger is that make some of these products dangerous for some systems and harmless in others.