Obviously I know bacteria and myco's are different; Im a professional mycologist.
From Botanicare Website:
"Bacillus root inoculant
From seedling to harvest, optimizing the size and health of your roots is the first step towards maximizing your plant’s yield. By creating and maintaining an ideal environment surrounding the root zone, whether in hydro or soil, you can effectively increase root tissue production and efficiency.
Hydroguard® contains unique beneficial bacteria, Bacillus Amyloliquefaciens, selected specifically for its superior ability to enhance the symbiotic relationship between the roots and their surrounding medium. During the plant’s most intense growth phases (i.e. transplant, transition, and heavy flowering), the demand for certain nutrients and essential trace elements increase and change frequently. To reach their full potential, plants require highly available forms of nutrition only possible through microbial mechanisms. Although plants generate some of these microbes on their own, supplementing with Hydroguard significantly increases and accelerates these mechanisms. This immediate boost of natural microbial activity in the root zone enhances nutrient availability that results in larger, higher quality fruits and flowers.
There is a direct relationship between the health and size of the roots and the overall health and size of the plant. Healthy roots allow the plant to uptake what’s required to achieve full genetic potential. Hydroguard is a beneficial bacterium that increases the size and density of the roots’ mass, and nutrient uptake.""
No where in there does it say used for reservoirs; it says its used to boost growth by enhancing the rhizosphere through symbiotic relationship with microorganism. The exact same concept of applying mycorrhizae. I was saying in regard to healthy plant growth, that resources seem better spent on a product which actually provides a visual boost in vigor, proved both anecdotally and scientifically. Which is also not NPK or plant food by the way,and significantly alters plant performance/appearance.