Danner Clearguard UV Clarifier Replacement Sleeves (Gen 1 & 2) Model:9 Watt Sleeve - Gen 2 you can easily add cinder

you can easily add cinder blocks (or similar) to sink the tubing

5" rotational ball output

this protector allows pond and garden plants to grow unobstructed

Aquascape Cold Water Beneficial Bacteria also reduces ammonia

Danner Clearguard UV Clarifier Replacement Sleeves (Gen 1 & 2) Model:9 Watt Sleeve - Gen 2 you can easily add cinderReplacement sleeves for 9W and 18W (Generation 1 2018 and before; Generation 2 2019 and after) Clearguard ultraviolet clarifiers. Ultraviolet light is used to clarify green water by killing bacteria and algae without harming your fish or plants. Make sure that your Clearguard filter continues to function with replacement sleeves. 100% designed and made in the USA!