Gordon's 3211072 PondMaster Watercolors Lake & Pond Dye Shimmer Blue, 1-GallonFor use in ponds, lakes, fisheries and ornamental bodies of water. Contains blue colorant, imparts an inviting shimmer blue color to lakes and ponds. May be immediately used for fishing, swimming, irrigation and watering livestock. Treats 1 acre of water 4' deep, use at 32 oz per acre foot of water. Size: 1 gallon Contains blue colorant, imparts an inviting shimmer blue color to lakes & ponds Kills aquatic weeds & algae in farm ponds High performance