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Synergy Reef

16″ Shadow® Overflow V3 2500 GPH

16″ Shadow® Overflow V3 2500 GPH

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MSRP $249.99

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Regular price $188.88 USD
Regular price $249.99 USD Sale price $188.88 USD
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What is the Shadow® Overflow?

The Shadow® Overflow is a device that is used to divert water flow from your aquarium into your filtration sump. This overflow can be used on any Freshwater, Marine or Reptilian habitats.  There are no limitations on where you can use this overflow system.

Synergy Reef Shadow® Overflow: Revolutionizing Aquarium Filtration
Experience the ultimate in precision and quality with the Synergy Reef Shadow® Overflow, a 100% injection-molded system designed for seamless integration into your aquarium. Perfect for tanks from 10-400 gallons, our innovative overflow system accommodates flow rates from 400-2500 GPH and features:

A Proudly American Product
The Synergy Reef Shadow® Overflow is a testament to our dedication and perseverance. Designed and manufactured by Synergy Reef Systems, this overflow system represents a new standard in aquarium filtration. Experience the perfect blend of form, function, and performance.

What's Included?

Includes the following with the kit:

  • Front Overflow Box
  • 1 Removable Polycarbonate Locking Front Weir
  • 2 Polycarbonate Bulkhead Nuts
  • Seamless Rear Box with 3 x 1.5″ Slip fittings
  • Locking Polycarbonate Rear Lid Cover
  • 2 U-Flow™ 90º Fittings
  • 4 Gaskets
  • Drilling Template (V1 and V2 are the same hole pattern)

Key Features of the V3 Shadow® Overflow

  • Removable Sealed Rear Lid and Rear Box Design – Rear Lid and Rear Box flange makes a watertight seal. This helps completely reduce salt creep formation on the exterior box.  The V3 Rear lid and Rear box is virtually watertight and prevents any water from exiting the box. No other overflow on the market has this capability.
  • 1.5″ Exterior Box Slip Fitting Openings – The 3 x 1.5″ Slip fitting openings in the rear box. This gives you maximum flow with a very small external box footprint. The smallest external box to flow rate ratio available. These can easily be reduced to 1" or smaller if needed!
  • Re-Engineered Polymer Construction – The Rear Box Material has been changed to a proprietary new polymer blend! This new polymer allows you to use ANY type of PVC or ABS glue or primer you choose.  This means that you can use any PVC Cement that you can find locally or have on hand already. It also makes the rear box even more durable than before!
  • Quiet Flow™ Weir design – The Shadow V3 now has a redesigned weir that makes it the quietest front weir box available. We have re-engineered the front internal box and designed an integrated Quiet Flow™ system. This allows for the same high surface skimming capability with no noise from internal flow pumps or wave makers.
  • Ultra Slim Profile - The ultra slim compact design means that there is no intrusive box inside your aquarium. Even the outside rear box is compact and will not be seen!
  • Fail-Safe Operation - With the 3 pipe design, there is no chance for a "overflow" of your aquarium, pun intended! The Safety features built in allow for a worry free system!
  • Upgrade-able! – Our Current Shadow V1 or V2 customers can easily upgrade their overflows to the V3. V2 Customers can easily upgrade without any re-plumbing of your system. And The V3 will be upgrade-able with any future advancements.

Unlock Superior Filtration with the Synergy Reef Shadow® Overflow

Our overflow system is the outcome of extensive testing and development, establishing a new benchmark for aquarium filtration. Experience a seamless, plug-and-play solution and learn why the Synergy Reef Shadow® Overflow is favored by aquarium enthusiasts. Eliminate bulky overflow boxes for high flow rates in a compact design.

The Story Behind the Synergy Reef Shadow® Overflow

Our Story - As passionate reef hobbyists, we knew firsthand the frustrations of traditional overflows: bulky designs, loud operation, and limited flow rates. So, we set out to create a game-changing solution. In 2011, we began designing the Ghost Overflow, which would later become the Synergy Reef Shadow Overflow, and over the past decade, we’ve rigorously tested and refined our vision.

A Decade of Innovation and Refining - Our goal was clear: to craft a low-profile, quiet, and high-flow internal overflow box that would meet the demands of discerning reef enthusiasts and aquarium hobbyists. We leveraged cutting-edge 3D software to push the boundaries of innovation, incorporating features that would have been impossible to achieve by hand. Through extensive testing and iteration, we’ve perfected our design.

From Prototype to Perfection - Initially, we handcrafted each overflow using flat acrylic sheets, but this method had its limitations. To make our vision accessible to all, we incorporated the use of injection molding, a process that no other manufacturer has adopted. While others still rely on outdated methods to build their copycat versions, we’ve raised the bar with our cutting-edge design. This allows us to mass-produce our overflow with precision, consistency, and unparalleled quality.

How is it installed? What do I Need?

This is a self-install kit. You can drill the tank yourself or have a aquarium builder do it for you and install this yourself! Instructions are located here: 16″ Shadow® Overflow Installation Manual

Drilling template is included with the overflow and we recommend you use the template when the overflow arrives to align it perfectly. But if you need the drilling template .pdf it is located here: 16″ Shadow Overflow Drilling Template

A Proven Track Record

A Proven Track Record

With over a decade of testing and refinement, the Synergy Reef Shadow® Overflow has proven itself to be a reliable and high-performance solution. We’re proud to offer a product that has been battle-tested in various aquarium environments.

Evolution to the Shadow® Overflow

As our design evolved, so did its name. We rebranded the Synergy Reef Shadow Overflow® from the Ghost Overflow in 2014, reflecting its sleek, low-profile design that seamlessly integrates into your aquarium.

Q&A

Q. – What tank thickness will the Shadow Overflow work with?
A. – .25″ (6mm) to .945" (24mm) Glass and Acrylic Tanks

Q. – What is the flow rate?
A. – Max. Flow Rate is 2500GPM. The 16″ Shadow Overflow can be used on tanks as small as 10 gallons up to tanks as large as 400 gallons. Each 16″ Shadow Overflow can handle as little as 150GPH or up to 2500 Gallons Per Hour! So if you need more flow, just add more overflows!

Q. – What size aquarium will the 16″ Shadow Overflow work for?
A. – This is a great question and has many answers. The size of the aquarium is not what matters, it’s the amount of flow that you plan on running to your tank from your return pump. The 16″ Shadow Overflow can be used on tanks as small as 10 gallons up to tanks as large as 400 gallons. Each 16″ Shadow Overflow can handle up to 2500 Gallons Per Hour! So if you need more flow, just add more overflows!

Q. – Can this be used with freshwater aquariums?
A. – Absolutely! We have thousands of freshwater customers that use the Shadow Overflows. Any aquariums that will be using a Sump under the aquarium will work.

Q. – Why don’t you offer larger front boxes like a 24″?
A. – We have with our extensive testing over the last 10 years (remember we did invent this type of overflow) that longer weirs actually are not efficient and actually can cause stagnant water to form inside the front box of the overflow. The 16″ size is the most efficient at draining with the 2 1.75″ drains in the rear of the front weir to the rear box. It also is a more compact size for your tank so it is less intrusive.

Q. – What is the difference between the 16″ and 20″ Overflows?
A. – The major difference is the 16″ is injection molded. This makes for a much higher quality and durable product. The 20″ is hand built from acrylic and only made to fit on tanks with glass/acrylic thicknesses of 3/4″ to 1.5″. The 20″ Overflows DO NOT fit on tanks with thicknesses less than 3/4″.

Q. – If I need more surface skimming, is a overflow with a longer than 16″ weir better?
A. – NO! This is actually not the case. Most people believe that a longer front weir makes more surface skimming. This is incorrect. Surface skimming is determined by how much flow goes thru the overflow, not the weir’s length. Water flow or Flow Rate is what determines the surface skimming of your overflow. This is determined by the hole size going thru the tank, not how long the weir is.

Q. – Can the front weir (teeth) be removed for periodically cleaning?
A. – Absolutely! The front weir (teeth) are snap fitted into place and easily removed for cleaning. You can also purchase a second one as a spare or to use when cleaning the main one. You do not have to turn your aquarium off when you remove the weir either! Your aquarium will still run perfectly normal when the weir is removed, unlike other overflow designs on the market. The weir is also locked into place so it will not fall off while installed on the front box.

Q. – Do I need to upgrade if I own a previous version of the Shadow Overflow?
A1. – If you own a Shadow V1 with a serial number from 0000-5000, You will need to upgrade the front and rear box for all of the V3 Features. You can also just upgrade the rear box from the V1 to the V3 to get the benifits of the sealed rear box lid and other V3 benefits.
A2. – If you own a V2 with a serial number from 5001 and up, you do not need to upgrade anything. The V2 and V3 components are exactly the same. The only part you would need to make yours a V3 would be the new internal plate for the front weir box. Contact us for an upgrade link.

View full details

Installing the Shadow® V3 Overflow Kit

Customer Reviews

Based on 29 reviews
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D
Dominic Derome

For large aquaria this is the only overflow that can handle high gph in a single unit.

D
Dominic Derome

Very well crafted unit. High quality overflow

S
SPReefs Seth Pope
Great Product

Works flawlessly for my 310gal aquariums. Only need one gate valve to fine tune the sound out of the drain. Quality product. Highly recommend.

S
Steeve Messier
Quietest overflow system!

I've been using the overflow for over a year now and am really enjoying the very low noise the box is outputting altough I am running a lot of flow through it! Surface skimmer is perfect and cleaning is very easy. Great design!

J
Jose De La Cruz
Good product

Good an consistent construction, easy to assemble. And thr dimensions from the website were accurate.