Aquashade Blue Pond Dye - 1 Gallon EPA-Approved Sunlight Blocker for Algae - Weed Suppression - Safe for Fish, Livestock and Swimming - Eco-Friendly Liquid Treatment for Water

This stuff is pricey but it works very well. It keep the water crystal clear as long as you keep treating. Our pond is 0.6 acre with 4 acre feet of water. I add one gallon every 3 months even in winter. Sometimes heavy spring rains requires an additional gallon.

I have used cheaper brands that are not as good. Never been disappointed with this brand. Great lasting color.

Pricey but seems to be the best color and lasts the longest. I've tried the cheaper pond dye but came back to Aquashade

Works well for keeping algae out of our pond. Have used for many years

Trying nearly all the Pond Colorants out there, we like Aqua Shade the best. It stays during all seasons if you use enough, lovely ice frost blue color in cold weather. It seems to do a better job at the price than other brands, quieting the algae growth spurred on by the sun. Put it in as soon as Spring warmth hits. Does not harm fish, cats dogs, horses drinking from source, nor does it bother pond fish - not sure about Koi fish though. Pour freely - I take a plastic cup & throw smaller amounts into water in various spots w/wind will left to stir it around. Use a set of rubber gloves as this product gives you "Blue Man" hands only Clorox will wash out. I use about 3- 4 gallons a year in a .275 (just over 1/4 acre) pond. Good stuff!