CrystalClear® KnockOut Plus

All Natural Fish Treatment

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  • 1 Gallon
  • Item: CC136-1G
  • $89.99

Remedies Single-Celled
Treats Ich &
Fungal Infections
Future Infections
Safe for
All Aquatic Life



Koi Pond

CrystalClear KnockOut Plus is an all-natural, fish treatment that eliminates plus prevents external single-celled parasites, ich (ick), and fungal infections. KnockOut Plus works extremely well with pond fish species such as koi and goldfish and unlike most fish treatments, there is no need to remove your filters before treatment. Furthermore, when used routinely, KnockOut Plus works as a strong preventative treatment. Use anytime new fish are added, during pond clean-outs, during spring start-up, or any time fish are stressed.

KnockOut Plus is a broad-spectrum treatment for a variety of parasites including ichthyophthirius (Ich), sporozoan parasite, dinoflagellate infections as well as fungi such as saprolegnia, achlya, leptomitus and pythium. It may be used with most invertebrates including snails.



Video - KnockOut Plus
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Fish Care
Product Label - 1 Gallon

How to Use

1 Gallon
Application Liquid
Temperature Restriction None
Gallons Treated
up to 7 Days
Shelf Life 2-Years


Pond Size
KnockOut Plus
Up to 60 1 Ounce
Up to 120 2 Ounce
Up to 240 4 Ounce
Up to 480 8 Ounce
Please note: Above are recommendations. Always read the product label.

Standard Application Rate

Shake well before using. Upon discovery of infection, apply 1 ounce of KnockOut Plus for every 60 gallons of water daily for 7 consecutive days. When there are no visible signs of infection, it is recommended to continue treatment daily for an additional 3 days to ensure infection will not return. Disperse over the majority of the surface area of the pond.

Persistent Problem Application Rate

Shake well before using. For infections that last more than 7 days after standard application, treat twice per day. Apply once in the morning and once in the evening. Do not apply as a bath application. KnockOut Plus works best as an in-pond additive.

Preventative Application Rate

Treat daily for 7 days anytime new fish are added, during pond clean-outs, during spring start-up or any time fish are stressed.

Product Notices

Do not use other chemicals in the pond while treating with Knockout Plus.


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Item Numbers and UPC

Item Number
UPC Code
CC136-1G 811262017275 1 Gallon

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