CrystalClear Algae D-Solv EPA Registered Pond Algaecide, 16 oz | Fast-Acting algae control for fountains & outdoor ponds containing koi & other fish, 16 oz treats 5,760 gallons.

Works great! I’ve had trouble in past years with my numeral pond getting a lot of algae build up. It’s aerated but still gets brown/green from debris. This only takes a little bit per gallon and it clears quickly with no foam build up on the surface like other products I’ve used. Most of the sediment is at the bottom which is easy to clean out or leave depending on the look you want but the water is clear. Very easy to use to solve a big problem.

This was recommended to me to The Pond Guy. We had some extensive work done on our pond this past spring, and the people who did the work also said they’d clean our pond… they used a pressure washer. A real no-no, as the spray is too harsh and washes off all the ‘good algae’. A plain garden hose would have sufficed and been far better. Anyway, flash forward 8 weeks and I had the worst string algae ever. So thick… I used a stick to pull up globs every morning, and that didn’t touch the issue. It just got out of hand. Our pond is small – only 500 gallons. I used 1-1/2 ounces - first I cleaned a bucket very well, then dipped it into my pond and collected a bit of pond water. Then I added the Algae D-Solv to the pond water, swished to mix, and gently poured it into our pond. I repeated this every 3 day, for a total of 3 times. After the 3rd day of the 3rd treatment (12 days later), there was NO string algae. None. Of course, throughout the treatment I did have to clean the pond, the filter, and skimmer daily. Also, I have 2 falls, and added 4 bubblers while I treated the pond, for added aeration, which helps. Unfortunately, it left my pond very turbid. I couldn’t see the fish, or anything. Tried water changes – several. Added beneficial bacteria (unnecessary). No help. Finally ordered CrystalClear RapiClear Liquid Flocculent – one treatment did the job. After that, I occasionally treat the string algae, once, which does the trick, and several days later add the flocculent. I have comets and shubunkins, and because I know my pond’s correct volume, they were never harmed, nor were my water lilies, hyacinths, or other pond and bog plants. I also had a couple comet fry, and they are fine. Not a fan of adding anything to my pond. I'm a big believer in letting nature do it's thing. But sometimes the pond needs a bit of human intervention to keep it healthy. UPDATE: The weather has cooled off here, and this product does not work as well in cool/cold weather, BUT it does work - you need to give it time. My string algae started to return so I did 3 treatments, adding the D Solv every 3 days. After the 3rd treatment I just gave the pond a few extra days and sure enough, it's totally clear of string algae once again (average nighttime temps are in the low 50's and I've stopped feeding the fish, of course).

My pond is about 300,000 gallons and was full of blanket weeds so i took a risk and spend good money on 2 2.5 gallons cans. I used sprayer to spray it evenly on the water. Before that i manually removed 10 carts of weeds and spend at least 10 hours on that After 2 days i see that rest of the weeds got brown and after 5 days disappeared but water became very muggy and with oil film on surface. Probably max 2 foot visibility - that is why 4 stars because they told it will be crystal clear. May be it is from dead weeds on the bottom Only after couple of good rains it became more clear. Also i see that other kind of weeds are slowing down - will see in few weeks

I use this stuff a few weeks ago and all 12 of my koi fish got really lethargic for a day or two and wouldn't eat then they got active again and the water cleared up fairly well but not perfect. I administer a second time a few weeks later and came home to clean my filters and all of my koi were floating belly up all 12 of them.... they were all dead within hours some of them were very healthy older fish. I would recommend a different product and use small small doses even less than what's recommended as a test.

This product does exactly as states and I wouldn't use anything else was extremely pleased I found it on Amazon and would highly recommend Fred Great value, keeps water clear, and is safe for your fish shipping was within 24 hours extremely pleased Fred

It works very well but the bottle has a crack in the bottom from shipping. We can still use it though.

I have Administered 3 doses to my small pond and have not seen much of an improvement. The directions on the bottle are also rather useless as they don't even explain how to Administer the product. I used directions from a product i used previously.

I really liked this stuff it works well on my fountain. But I won’t order it again because my last order was empty from the bottle, top was not on tight and it all spilled out into the plastic bag. It was a mess. I just had to throw it out. But this was the best stuff I have found to keep the algae out of my fountain.