I did a search on safety of the product and found this about storage:
H. WINTER ISSUES:
H1. Do I need to worry about Microbe-lift products becoming unusable if they get frozen over the winter? Can these be stored in the garage over the winter season, or do I need to bring them inside?
The MICROBE-LIFT products, such as the liquid bacteria, will remain viable once they thaw, if frozen. However, they will lose some viability, about 10%, with each freeze/thaw cycle, so it is better if they do not freeze at all.
H2. Should the products be used during the winter months?
MICROBE-LIFT products can be used continuously all year, even if used under the layer of ice. If there is a layer of ice on the pond a heater or de-icer can be used to maintain a hole in the ice for gas exchange. Otherwise stimulating biological activity can be detrimental. If the products are under icy water they will continue to work, however they will not proliferate at the rate they would at 65-70ºF.
H3. How should MICROBE-LIFT products be stored?
A cellar, garage or shed should provide the necessary protection. The ideal storage temperatures are between 40-105ºF.
I. SUMMER ISSUES:
I1. How should MICROBE-LIFT products be stored?
Products should be protected from extreme heat and direct sunlight. Live Microbelift microbes can withstand heat up to 105ºF before starting to die. A cellar, garage or shed (but not in an attic in the shed) should provide the necessary protection during summer months. The ideal storage temperatures are between 40-105ºF.
I2. Does the water need to be a certain temperature for the bacteria to work?
For MICROBE-LIFT/PL, Professional Blend Liquid, Ensure, TheraP and Sludge Away, the temperature should be 45ºF or above. For ML/ Autumn/ Winter Prep, the bacteria are psychrophiles, low temperature strains, that are active below 45ºF.
J. PRODUCT FRESHNESS / STORAGE / SHELF LIFE
J1. How should MICROBE-LIFT products be stored?
Products should be protected from extreme heat and direct sunlight. It can withstand heat up to 105ºF before starting to die. A cellar, garage or shed (but not in an attic in the shed) should provide the necessary protection during summer months. The ideal storage temperatures are between 40-105ºF
J2. What is the shelf life for the liquid bacterial products?
Approximately 2 years in unopened container, 1 year after being opened if stored properly.
J3. Is there a listing of expiration dates on products?
No, they do not list expiration dates on the products. There is a batch number on each that can be traced when necessary. (See shelf-life for more information.)
J4. What is the shelf life of the dry products such as the enzyme products?
All of our dry biological products, and the dry bio-products with added enzyme and other support material have an extended shelf life well beyond our two year stated claim. The dry formulations consist of multiple strains of spore forming microorganisms and these microorganisms can stay in the spore form (dormant state) for an indefinite period of time when properly stored. The method of microbial activation is two fold:
a) the addition of water;
B) the presence of waste organic matter.
Both of these factors are required to active the microbes and get their biological oxidation process going. Without these they remain dormant but viable.