OM2500 HOB Overflow Box - Skimz

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OM2500 HOB Overflow Box - Skimz

100% Recommend this to a friend (1 of 1)

SKU: 210428
In Stock: 24
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Quick Overview

Max Flow - 660 GPH

Skimz External Overflow Boxes are a great addition for tanks that do not currently have a drain system. Adding a sump to a tank is super easy with the Skimz OM2500, just place the hang on back overflow box onto the edge of your aquarium, and using 1 1/4" soft vinyl tubing you can plumb the box to a sump. The durso style valve lets you fine tune the overflows drain rate, making it completely silent.

  • Removable Weir

  • Durso Style Drain System

  • Compatible with Aqua Lifters

  • Integrated Priming Nipple

  • Leveling System


Full Details

External overflow boxes give you the ability to add a sump or added filtration to your aquarium without the complication of drilling your existing aquarium. On many ocassions we have set up tanks and then a few months after decide to add a sump. With an established tank, drilling and plumbing the aquarium isn't really an option. All HOB overflow boxes work off a siphon principal, pulling water out of your aquarium, over the edge and the directed into a bulkhead that is included with the OM2500.


Noise of a large concern for all types of overflows and the OM2500 uses a durso style wedge pipe that allows you to tune the drain flow by just turning the wedge pipe until the noise stops. We do not recommend using DC return pumps with overflow boxes since they have variable flow, and once the overflow box is tuned the return pumps flow rate should not be increased. 


Note - We highly recommend using an Aqua Lifter pump to prime the overflow box continuously. The Aqua Lifter pumps are a cheap insurance policy against siphon restriction through the overflow box.



Max Flow - 660 GPH

Max Tank Thickness - 2"

Dimensions - 7.28" L x 7.28" W x 9.50" H

Water Intake External Dimensions - 7.28" L x 1.5" W x 4.5" H (height is variable for leveling)

Minimum Clearance Required Behind Aquarium - 5"

Plumbing Connection - 1 1/4" Soft Tubing (we recommend braided vinyl tubing)


What's Included?

1x OM2500 Overflow Box

1x Removable Weir

1x Priming Tube

1x Priming Tube Valve

1x Drain Valve Assembly

3x Leveling Screws


1 Item

  • Amazingly SILENT overflow box!! By Kneppnasty on 5/3/2017

    After having decided to run my new tank as a peninsula configuration, I didn't want to drill it and be forever stuck that way.....
    So I used a CPR CS-90 continuous siphon overflow on my tank for the past 1.5 years with few complaints. Since I happen to have a Skimz sump and protein skimmer, I have seen pics of these Skimz overflows on the internet for quite a while now....but nobody in the US seemed to be selling them.....Until BRS recently started carrying them.
    Sooo I figured that I would order one and give it a shot....

    Let me tell you- I've had it running on my tank for a few weeks now and I TOTALLY LOVE IT.
    It runs dead silent and without a single hiccup, especially compared to the CPR overflows.
    The removable weir feature is totally clutch, because it was a royal pain to scrub clean when permanently connected like the CPR overflows.
    I simply cannot get over the noise reduction since switching to this overflow, it's incredible! And not only does it feature an adjustable flow rate, there is a built in silencer inside the adjustment tube, exactly like a protein skimmer air intake silencer. (Def makes a difference!)

    The only little thing I have noticed is that the 1/4" plastic elbow going into the top of the unit (used for priming) sticks down into the overflow cavity about 1/8" and is not flush with the top/inside the same way it is with the CPR overflows. This results in a small air pocket accumulation inside the unit that constantly remains there because the aqua lifter pump will start drawing up water before all of the air pocket is sucked out. It seemed like this would cause an issue and result in lost siphon eventually....however it HAS NOT resulted in any issues whatsoever. So maybe Skimz did this on purpose for some reason? Not sure, but regardless, it has performed above and beyond my expectations and I would highly recommend these overflows to anybody not looking to drill their tank and make permanent alterations.
    Nice work Skimz! Thanks for another quality product!


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