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Red Sea

Reefer 3XL 900 Rimless Aquarium 240 Gallon (Black) - Red Sea


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***3/29/2021 HOLIDAY UPDATE*** Red Sea's offices will be closed this Friday, April 2nd, in observance of Good Friday. As such, all dropship aquariums will be shipped on Thursday, April 1st. Any orders placed after Wednesday morning on March 31st will not be shipped until the following Friday, April 9th. Thank you for your understanding.

SHIPPING INFORMATION: Red Sea aquariums are shipped directly from the manufacturer to you. Orders placed by 10pm Wednesday are shipped on Friday. Red Sea tanks can only be shipped within the USA to the 48 contiguous states. The shipping carrier will contact you by telephone to schedule a convenient delivery date after you place your order.

Red Sea is expanding their range of REEFER™ systems with 4 new models which still maintain the familiar rimless format and clean lines of the REEFER series. The impressive, 900 liter / 240 gal. REEFER 3XL 900 model offers hobbyists the freedom to create a truly spectacular reef. 200 cm / 79” long, and 65 cm / 25.6” high and wide, the 3XL 900 introduces an enlarged overflow box with dual side-facing return pump outlets and increased surface skimming that provides ideal water circulation in the tanks with flows of up to 10,000 lph / 2600 gph. These new features have also been implemented on the latest version of the XXL 750 V3 giving it a new look and significantly improved flow dynamics. Both of these systems come complete with fittings to attach either a single or dual return pumps.

A unique feature of the 3XL 900 is a split sump system that provides unsurpassed flexibility. The main sump is set for the usual filtration functions with an optional refugium chamber and a dedicated adjustable height skimmer chamber. The sump extension (60 liters/ 16 gal.) can be connected to the main sump and used for additional filtration, as a larger refugium or even as a dedicated frag tank. Alternatively, it can be set up as an independent unit and used as a full-size (83 liters / 22 gal.) RO reservoir or saltwater reservoir for automated water changes.

4 new REEFER™ models, dramatically expanding the range of its premium reef-ready aquariums to include the XL 200, XL 300, XXL 750 V3, & 3XL 900.

Furthermore, as part of the continued commitment and support of its aquarium systems, Red Sea is enabling all first buyers to register online to extend the standard 2-year warranty on all aquariums for an additional 1 year at no cost.

Features of the Red Sea REEFER™ 3XL 900 include:

  • Rimless, ultra-clear, beveled edge glass aquarium
  • Elegant, reinforced plywood marine-spec cabinet with aluminum support
  • Dual side-facing return pump outlets with fittings for one or two pumps
  • Enlarged overflow box for increased surface skimming
  • Unique split sump system for unsurpassed flexibility:
    • Professional refugium-ready main sump with variable height skimmer chamber and micron filter bags and media cups.
    • Extension sump (60 liters/ 16 gal) can be used as a dedicated frag-tank or refugium. Alternatively, it can be disconnected and used as an independent reservoir of 83 liters / 22 gal.
  • Silent, regulated down-flow system with emergency overflow
  • Integrated automatic top-up system with reservoir
  • Assembly-ready piping – no gluing required

Reefer Model Comparison:

XXL 750 v3

3XL 900

Main Features

Ultra Clear Front
and Side Glass:
Front Glass Thickness: 3/4" (19 mm) 3/4" (19 mm)
Enlarged Built-In
Surface Skimmer:
Integrated ATO System:

System Volumes

Display Tank
Water Volume:
160 gallons
600 liters
192 gallons
720 liters
In Cabinet Sump
Water Volume:
40 gallons
150 liters
48 gallons
180 liters
Total System Water Volume: 200 gallons
750 liters
240 gallons
900 liters
RO Reservoir: 7.6 Gallons (28.7 L)

System Dimensions

Display Tank Length: 71" (180cm) 79" (200cm)
Display Tank Height: 23.6" (60cm) 25.6" (65cm)
Display Tank Width: 25.6" (65cm) 25.6" (65cm)
Total System Height
with Cabinet:
58.3" (148 cm) 60" (153 cm)

Sump Dimensions

Water Height: 8.3 - 10.6"
21 - 27 cm
8.3 - 10.6"
21 - 27 cm
Skimmer Chamber
w/o Refugium Wall:
25.6 x 20"
65 x 51 cm
17.7 x 20"
45 x 51 cm
Skimmer Chamber
w/ Refugium Wall:
25.6 x 11"
65 x 28 cm
17.7 x 11"
45 x 28 cm
Return Pump
13.7 - 11"
35 x 28 cm
13 - 11"
33 x 28 cm
Extension Sump: 20 x 16.5"
51 - 42 cm

Return Pump

3/4 Threaded Hose Barb
Pipe Int. Diameter:
1" (25 mm) 1" (25 mm)
Recommended Flow Rate: 2640 gph
10000 lph
2640 gph
10000 lph

New Special Features

Adjustable Height
Skimmer Chamber:
Dual Side-Facing
Return Pump Outlets:
Split Sump System:
Refugium Ready:
225 Micron Thin-Mesh
Filter Socks:
2 2
Filter Media Cup: 2 2
Quick Release Cabinet
Door Hinges:
Heavy Duty Levelable
Plywood Cabinet:

Manufacturer Info

With a dedicated team of scientists and other professionals, Red Sea is widely recognized as a leading innovator and manufacturer of quality products for aquarium hobbyists. Red Sea constantly strives to provide hobbyists of all levels with highly effective solution-driven products designed to make your fish-keeping experience as enjoyable and successful as possible.

The embodiment of Red Sea’s dedication to providing solutions for today’s reef-keepers is its range of MAX-NANO, MAX-E & MAX-S aquariums- The only choice for true Plug & Play™ coral reef aquariums, now featuring the very latest in LED lighting technology.

For advanced reef-keepers the Red Sea REEFER provides a great platform into which you can add your own selection of hardware. With its ultra-clear glass, ATO built-in, silent flow valve and superb quality of finish the REEFER sets the standard for those wishing to customize. REEFER is also available as a Deluxe version with LED lighting included.

Red Sea’s unique Reef Care Program (RCP) provides a comprehensive, safe and easy to use program for testing and supplementing within reef aquaria, and is perfectly complemented by Red Sea’s Coral Pro & Red Sea Salt’s, which has become the salt of choice for those seeking the very highest quality water quality for their coral reef aquariums. Both salts are made using a unique natural process which delivers unrivalled homogeneity and is perfect for delicate corals. Check your individual bucket of salt’s composition using Red Sea’s innovative new “MyBatch” software.

Whatever your aquatic needs, Red Sea delivers high quality innovative, solution based products.

Ask a Question Earn 15 Points when you answer a question
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9 Questions
Displaying questions 1-9
How much does the stand and tank weigh dry
Asked : Feb 09, 2021
By : Thaddaus , Savannah
Unfortunately, we do not have the weight available. If you reach out to Red Sea directly, they should be able to provide you with it.
Answered : Feb 10, 2021
What is the size of the pipes?
Asked : Mar 26, 2020
By : Brandt Kemmerer, Iowa

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