Active ingredient is Barley Straw. When Barley Straw is put into water, it begins a
decaying process and releases lignin which then interacts with algae and causes
it to die. Completely safe and effective treatment contains no chemicals,
pesticides or herbicides; no toxic side effects. Can be used with cattle, goats,
sheep, swine, all breeds of horses, poultry, fish and even exotic animals. Also
great for automatic waterers, bird baths, ornamental ponds and fountains. Easy
to use; just place one unopened burlap bag in tank. One bag is good for an
average 200 gal stock tank. For larger or extremely dirty tanks, use two bags.
Begins working immediately but may take 7-10 days to notice its effects. Scoop
out any floating debris. Replace every two mos. Burlap bag is completely
biodegradable. $6.95 plus $2.95 Shipping