First product review here so bear with me. I'll use a subjective 1-5 scale for key areas.

The basic specs

Neptune Systems COR-20 pump
2000 GPH
No Apex required

My use and thoughts.

Packaging and Presentation:
5 ... no question Neptune has it down when it comes to packaging and presentation. Considering the cost this should be a given. Included are fittings and o-rings, hex key, getting started sheet, pump, control unit, power supply and USB (Aquabus cable)

Build quality:
The pump itself feels solid and has appreciable heft. It does feel well made and that care and attention was placed in the build and assembly. The control unit on the other hand is incredibly light, feels cheaply made, and is not confidence inspiring in stark contrast to the actual pump. The buttons feel like they will break, overall the control unit just doesn't match up to the rest of the items.

My major concern is that there is no screen provided. Neptune's position on this is that any screen restricts flow and efficiency and that returning water should be clean and clear. I do not have a refuge in my setup but for those that do this could be a deal breaker.

Installation and setup:
This went into my first "big boy" tank, where I have an external sump. Due to the design of my sump, I had to add a couple of 45 degree elbows as the offset of the pumps return would have put the intake against the side wall of my sump, rotating it 90 degrees either directions also caused alignment issues. Can't fault Neptune for this as it's going to be impossible to account for every sump design out there.

Plumbing was straight forward for an unsupervised rookie. I did find the collar on the return side to be very short allowing only about 3/8 inch of pipe to be glued in. The connection is solid but could be challenging.

Connections were simple and the cord is adequately long to reach where my electronics are mounted in a cabinet a good 6-8 feet away. (cable runs the length of my sump, behind the stand, into the cabinet and still has a service loop. Connecting the pump to the Apex Jr was simple using the Aquabus cable.

The Apex setup task was pretty slick and intuitive, within 3 minutes I had configured the pumps normal operational speed, the lowest speed, and feed mode timer.


This pump is silent, powerful, and hassle free. In order to hear the pump I have to actually place my head down against my sump due to the volume of the drain overpowering it. Not a lot else to say, it does it's job very well.

With the ApexJr in place this is a fantastic pump. Feed mode restricts the flow to a stall requiring no gate valve to be in place, piece of mind with the pump shutting down in case of obstruction or low water level, and it's very quiet and efficient, I'm currently using about 38 watts driving it and turnover and flow seem to be great. I hope to add a flow sensor in the near future so I will have accurate GPH rates to report.

Overall if you are an Apex user and needing a 2000 GPH rated pump, I'd recommend putting this on your short list.

Overall Rating 4/5