Synergy Reef CL-34 Sumps


**********These sumps are built to order.  Current lead time is 3-4 weeks  ******************

34″ x 15″ x 15″ Synergy Reef CL-34 Sump Color Laminated

    Reset options

    Choose your exterior side colors

    *For Storm Cloud color, please select "All Clear" 

    *Choose what Drains you need.

    John Guest Fittings

    Please select how many John Guest fittings you would like installed. 

    *Filter Socks

    4" Filter Socks 100 Micron

  • Sock Silencer (set)*

    • 5 Gallon ATO Containers

      $194.99 $112.49$148.49

      5 Gallon Synergy Reef Series ATO Containers - Auto Top Off in style!

      BUILT TO ORDER ITEM- Current lead time is 1 weeks
      15" x 6" x  15" ATO

      5 Gallon ATO Containers

      • Exterior Wall Color*
      SKU: 5GallonATO

    • 16" Shadow Overflow V3


      MSRP: $249.99

      In Stock and ready to Ship! Shadow V3 Overflow Kit

      • Don't Forget to add these and SAVE Now!

        *63mm Diamond Hole Saw

        Used for drilling holes for the Overflow on Glass Aquariums (not for Acrylic). 

        *Additional Removable Weir

        *Internal Pipe Kit

        Internal Pre Cut Pipe Kits. Easy to install!

        *External Pipe Kit

        External Pre Cut Pipe Kits. Easy to install!

        Pump Return Parts and Tools. 

        *Overflow Loc-Line® Return Kits

        Single Overflow Loc-Line® Return Kit

        Double Overflow Loc-Line® Return Kit

        *Plastic Trim Spacer Kit

        - Used for plastic trimmed tanks if you want to have a higher water level above the trim. Only needed on a small amount of tanks. 

      In stock (can be backordered)

      SKU: Shadow16V3
SKU: CL34Sump Category:


Are you looking for the perfect sump that not only looks awesome, but has over the top performance? The Synergy Reef® CL-34 model sumps are your answer. We have designed this model to meet the demands of the reefer who demands more than the average off the shelf sump. We hand build each one to meet your needs. Need slight modifications in length to be able to fit this in your stand. Want it to flow right to left or left to right? We can do that! Try that with an off the shelf sump. The CL Series™ sumps feature a double color Cross Laminated™ euro brace. We only use the highest quality cell cast acrylics on our sumps. Built by Reefers for Reefers!

Available in Left to Right or Right to Left Flow Configurations (Shown in Left to Right)


  • Standard – Clear Sides and Back ***** If you would like the sides and back the to be matching Color , please select “Color To Match” in the Exterior Wall Color Option above. For Storm Cloud choose “ALL CLEAR”.  Storm Cloud will have White sides/back with a Clear Smoked front. 
  • Dimensions: 34″ long x 15″ wide x 15″ high
  • Skimmer Section: 17.5″ x 14.5″
  • Return Pump Section: 6″ x 14.5″
  • Total Water Volume: 31 gallons
  • Skimmer Water Level: 6″ to 10″ adjustable
  • Removable media tray in between the baffles use for filter pads and bags of media
  • Laser etched water level markings to allow easy setup of skimmer water depth from 6.5″ to 9.5″
  • Cross Laminated™ color Euro-bracing
  • High Quality Precision Machined Poly carbonate lids over Filter Socks and Return Pump areas
  • High Quality machine rounded and chamfered edges
  • Advanced designed Euro-bracing also has cord routing and Dosing connections built in
  • 4 x 1/4″ John Guest tubing holders for plug n play dosing / ATO connection
  • Drain Input Fittings: 3 x 1.5″ ABS Bulkheads (Allows Plug n Play with the (Shadow Overflow System)
  • Filter Socks Holders: 2 x 4″
  • Return section has 1″ Bulkhead
  • Made In The USA!!

MSRP: $699.99



Additional information

Weight45 lbs
Dimensions41 × 21 × 21 in
Stainless Thumbscrews

No, Plastic is fine., Yes, Adjustable Baffle Only (Qty.2)

Heater Holders


Exterior Wall Color


Return Bulkhead Size

, ,

Sock Silencer (set)

No, Yes, I do want matching sock silencers

Customer Reviews

Based on 6 reviews
Mike Weckbacher

I received my sump, the quality is amazing. You can clearly see the time they take and their professionalism. A quality American made product. Customer service was also great, timely email responses, and notifications throughout the build.

Synergy Sumps Are Like No Other – Simply Flawless!

Purchasing my Synergy sump was the best decision I have made in all my years of fishkeeping. I could write a book about how wonderful the Synergy sump truly is, but I will save everyone the micro details and focus on why you should consider buying a Synergy sump. In my opinion, Synergy sumps are on a whole other level and are the best of the best. I own several sumps from leading manufacturers; Fiji, Trigger, Eshopps, Waterbox, Red Sea, and others. When you look at the overall design, layout, and craftsmanship – from a distance, most appear to be quality, but this is where Synergy separates itself from the pack. Looking closely, Senergy sumps are refined and polished like jewelry - every dimension is spot on and square. Every seam, edge, hole, and cover represents perfection. You can tell their craftsmen take pride in their workmanship. Not only are Synergy sumps brilliantly refined, but the overall design layout, sectional space, flow, function, and hardware also shine with performance.
I researched sumps for a long time, and I was looking for one that would allow me to configure a custom filter room to support a new freshwater Discus display, and I am so thankful I purchased the Synergy CL-34 Sump. Online photos can be deceiving, but when you have a Synergy sump in your hands, Synergy is a world apart from the others. It gets better, Synergy is a family-owned business, and their products are made here in the USA. I received First-class customer service from initial ordering to updates along the build process to the final shipping verification. Other companies should take note. Synergy is a fantastic company - you can tell they have a mission: producing high-quality crafted products made in America while providing top-notch customer service. My Synergy sump has been up and running for months now, and I am pleased to say that my Synergy has performed flawlessly, and based on the overall craftsmanship, it might just outlive me. This is my honest review, and I have no direct relationship with Synergy besides being a customer. I have not received compensation or free products for leaving my review... Alan - Olympia, WA. January 2023

Tyler Sortino
Amazing quality!

All I have to say is WOW! Perfect for my 100g build. Amazing quality and amazing customer service. The sump is amazing and the attention to details is spot on. By far the best sump I’ve purchased. Will be a returning customer when another is needed

Tom s
Top notch

Reefing is a hobby of gear and if you’re like me you want your gear to look as good as your tank and you want to show it off.
You will not be disappointed!

Lord Imson
The best component of my new 100g build

TLDR: Awesome customer service and fantastic product!

I spent weeks researching sumps for my new 100g build, and especially hesitant to purchase a sump that is not off the shelf because of previous experiences with other companies. But from the moment I contacted Synergy Reef to inquire before purchasing, I knew I was in good hands. Their customer service is probably the best I have ever experienced. They are quick to respond with any questions (even my dumb ones) and it felt very personal, not just another 'customer'. The online purchase was very straight forward and intuitive, and the build status update was great, especially for people like me who are very impatient with online purchases. .. And the SUMP.. I cannot be happier with the build, quality, design, look, aesthetics, component placement, you name it. I find myself looking at the sump more than my display tank. I have absolutely zero regrets with working with Synergy Reef and will absolutely work with them in the future. Honestly, don't look further- they have the best product, cost, turnaround time, and customer service ratio.

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