Grading system is how whole the leaf is.. grade A means it's a good, solid leaf, B means it has a few holes, C more holes, ripped, etc. It doesn't really make a difference what grade you use, as most rip up the leaves as it is.
In airtight, ziplock bag (usually the freezer size), kept dry.
Can last for a very long time if stored properly and kept dry - can keep them for over a year.
You can plop a leaf (whole, broken up) into the tank, or can soak them in water for 24-36hrs and just use the tannin water they create, can make a "tea" with them which is basically just seeping them in hot water and creating the tannin quicker.
About every 2-3 weeks.. they start to disintegrate in about a week or two - but they are usually changed every 2-3 weeks.
If stored properly there should be no risks.. also purchase from a reputable dealer to ensure no pesticides were used near the tree.
Natural Anti-fungal, anti-bacterial and anti-parasitic.. helps strengthen immune system, fins and scales - will help heal wounds, torn fins, lost scales, etc. Lowers pH, helps relieve stress, stimulates color.. it makes the water look amber in color, how deep of a color depends on how much you put in. It simulates the "natural" water and many bettas prefer it. It stimulates breeding.
Depending upon size of leaf and size of tank it will depend on how many leaves to put in it. A typical 6-10" leave you would use 2 for every 10-15 gallons.
Last edited by Myates; 03-28-2013 at 09:21 AM.