1/4in Random Flow Generator for Fluval Spec V – RFG025-FSV


CLICK HERE to view the new 1/4in Random Flow Generator Return Line Upgrade Kit with single 1/2in Flex-Sereis Random Flow Generator® Nozzle


Incudes the new Flex Series Random Flow Generator®

RFG-FLXExtremely Durable and Flexible Material
Manufactured with a reef-safe TPU (Thermoplastic Polyurethane)

  • Creates a random flow pattern with no moving parts!
  • Designed for the Fluval Spec V Nano 5-gallon Aquarium
  • Easily onto stock outlet
  • Printed in Reef-safe PETG plastic. See our FAQ’s
Flow recommendations
The 1/4 RFG Nozzle is designed for small 5-gallon or less Nano and Pico aquariums. The "Optimal" GPH recommendation is just a suggested flow rate, so we encourage you to experiment
ModelMinimum GPHSuggested Optimal GPHRerecorded MAX GPH
Single 1/4in RFG (RFG025 )80-100120-140225
Two 1/4in RFGs (RFG025)120-150200 - 300400




The 1/4in RFG withe Fluval Spec V/Evo is easy to install. Simply remove the stock nozzle assembly and the included 13mm adapter slip-fits right onto the existing pipe.

  • Remove Stock Nozzle
  • Assemble the 1/4in RFG to the Adapter
  • Press the Nozzle/adapter assembly onto the pipe that protrudes out from the back wall, while supporting the elbow behind the back wall with your other hand.
  • Adjust the angle of the nozzle and or rotate the adapter to ensure the nozzle sits below the water line.


The 5 internal fins form a set of spiraling channels. As the water flows through the nozzle, the channels draw the stream of water in one direction or the other. The small amount of interference at the base of the eductor causes the stream to randomly change direction as it exits the nozzle.

Draws in additional water volume