Aquathol K is a ready-to-use, concentrated contact herbicide which dissipates quickly and leaves no residue. Although made with a similar active ingredient as Hydrothol 191, it is much safer and easier to use. It controls submerged weeds in lakes and ponds and the short residual contact time (12-48 hours) makes it effective in both still and slow moving water. Aquathol is effective on many weeds including hydrilla, milfoil and curly-leaf pondweed and begins working on contact to break down cell structure and inhibit protein synthesis. It can also be used in muddy water because it does not bind to suspended sediment or organic matter. It will not harm the environment, fish, birds or other aquatic life.