

🌿 Clear waters, zero compromises — own your pond’s pristine look!
Crystal Blue Copper Sulfate Algaecide is a premium 99% pure granular treatment designed for large ponds and aquatic environments. It effectively controls a wide range of algae species, especially during warm water conditions above 60°F, delivering rapid water clarity while requiring mindful application to protect sensitive fish.






| Best Sellers Rank | #12,254 in Patio, Lawn & Garden ( See Top 100 in Patio, Lawn & Garden ) #23 in Water Garden & Pond Treatment |
| Brand | Crystal Blue |
| Customer Reviews | 4.4 out of 5 stars 2,358 Reviews |
| Global Trade Identification Number | 00768980003335 |
| Item Form | Granules |
| Liquid Volume | 5 Liters |
| Manufacturer | Sanco Industries |
| UPC | 768980003335 |
M**H
This is a great product !
I have a 400 gallon pond with a waterfall and I always had an algae issue until I bought this. I know I poured a little too much in but I was thinking "what the heck". The pond was cloudy for a few days and then it cleared the water up and now it looks fantastic! Crystal clear. What a great product ! I would highly recommend this to anyone who has a pond with an algae problem !!!
F**Y
Copper Sulfate Algaecide
Does the job. Distribute through your toilets. Keeps those lines clear of roots as well as the septic itself.
C**E
Does what it says it will do
Works very quickly, easy to use. Wear a mask when spreading this! It got rid of a snail and parasite problem within hours!
A**R
As advertised
As advertised
M**B
Lasts a long time and the only thing thatprevents algae in my fountain
I've tried several different chemical options to treat my ornamental fountain in my backyard, and nothing worked until I used this stuff. Because my fountain is in the full sun, most traditional chemical treatments are ineffective and the algae blooms even when I dose at 2-3x the recommended treatment levels for my application. I had previously tried Tetra Pond Fountain Blocks, EasyCare Fountec Algaecide and Clarifier (worked somewhat in the spring but not the summer) and three of the AquaScape autodosing system treatments (Prevent, Control, Maintain). Not one of them worked, and I would typically have to drain and powerwash my fountain after 3-4 weeks to get a clean, clear fountain again. This stuff is AMAZING! There aren't doing instructions on the label for small areas like my fountain (this amount of chemical is enough to kill all the algae in a 10 acre pond), but you can find it on the internet. For my 500 gallon fountain, I put in 1.5 tsp every other week. I have had ZERO algae growth! This container will last me for many years, so it's not only incredibly effective, it's also really cheap. Everything I've read online would indicate it is safe for animals drinking the water, but it's not safe for fish.
P**T
Toxic to humans
Works with constant application, that being said, very expensive Make sure you don't touch or breath product.
L**E
Does what it is supposed to do.
Works well
T**G
Best product I have ever used to control algae.
I have a small garden pond (approximately. 450 gals.) with some lilies. No Fish. I have constantly battled with algae and green water every summer. I have tried many different products without success. This is the ONLY product that has worked for me. I used 1 Tablespoon diluted in 16 oz. of water. It does not seem to be harmful to the lilies at this time. I wish I had known about this product when I built my pond several years ago.
Trustpilot
1 month ago
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