Overall assessment: 4 out of 5

 The below links will take you directly to the ReeFlo website for more detailed information

http://www.reeflopumps.com/dimsmanuals.html

http://www.reeflopumps.com/lowspeedhighflow.html

This is one of the best external return pumps that I have tried.  Based on the manufacture’s stated flow rate, the reeflo return pump would have a maximum flow rate of up to 3600 GPH at zero head height. I would have no concerns using this pump for up to a 200 to 250 gallon aquarium (display tank size).  The wide range of flow rates is based on the options of using one of the two impellers that comes with the pump.  By using the smaller impeller, you will get lower flow rates and the pump will consume less energy.  Using the larger impeller will give you a lot stronger flow rates but it will also use more energy. The above link to the manufacture’s web site contains detailed information about the exact flow rates. The impellers are easy to change by disconnecting the plumbing lines and removing the impeller cover which also makes routine maintenance easier than most external return pumps. The use of different sized impellers is a very smart approach to balance energy consumption while allowing for future flow changes/increases without having to buy another return pump or making changes to your plumbing lines. 

The reeflo return pump is also one of the quietest return pumps that I have used and produces very low level of heat.  The fan built into the back of the pump is both extremely quiet and keeps the pump nice a cool.

The reeflo return pump takes a 2 inch input line and has a single 1.5 inch return line.  I also like the small overall size of this return pump for the flow it produces, measuring at: 11″ x 6.57″ x 7″ (L x W x H).  The reeflo return pump can also be a very expensive pump ranging in price from $350 to $450 depending on where you live in North America.

I have been using my reeflo return pump nonstop on a 180 gallon aquarium with a 100 gallon sump for about a year now without a single problem. Even though these pumps come at a high price, I would highly recommend them to anyone who is setting up a larger aquarium where a external return pump is best suited.  In my opinion, you will get what you pay for.