Protein skimmer Water flow out flow Water flow input Macro algea Fiji live rock Live sand layer Oolitic sand layer Crushed coral base layer Plastic screen mesh, divider layer Plastic screen mesh, bottom level Plenum system (eggcrate material) Return hose to main tank Shut-off / control valve Plumbing coupler #2 Plumbing coupler Circulation pump Refugium baffle overflow side Refugium baffle intake side Intake chamber divider Eggcrate bottom Bio-bale material Hose from main tank overflow

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Description of Sump / Refugium Elements

Flexible 1/2" ID reinforced vinyl tubing from overflow located in main tank.  Hose is held in place using a plastic wire management clamp bonded to the side of the tank.
Bio-Bale Biological Filter material (CPR Industries).  This is used primarily to reduce the splash of the water entering the tank after a vertical drop of approximately 9' from the tank above.
Removable bottom consisting of 1/2" eggcrate material.  Eggcrate rests on two strips of clear 1/4" acrylic 1/2" x 12" bonded to the side of the tank and the bottom edge of the baffle.  Clear silicon is used to bond the piece to the glass and the baffle.
Intake baffle box consisting of 1/4" clear acrylic approximately 4" x 8" x 17"h, bonded to the back and end of the tank using clear silicone. (Note:  use only silicone rated for aquarium use, general construction silicone can contain cyanide which may leach into the tank water). The bottom of the baffle is held 2" above the bottom of the tank and is held down 1" from the top.  By holding the baffle box down below the top edge of the tank any potential overflow will first flow into the tank and hopefully not the floor.
Main baffles consisting of 1/4" clear acrylic bonded to the front and back sides and bottom of the tank using clear silicone.  The top edge of each baffle has 1/8" wide slots 3" long spaced approximately 1/2" apart OC.  These slots create the top of the overflow between the chambers while creating a barrier screen to potential critters or other items to be contained with-in the refugium area.  An additional strip of 1/4" acrylic 1/2" wide can be boded along the top edge of the baffle to reinforce the slotted tops if desired.
Circulation pump.  This will need to be matched to the system  based on the individual requirements of each system.  Note:  While the diagram does not show a shut-off valve  at the intake from the tank to the pump it is strongly recommended that one be installed.
Coupler connections to allow disconnecting the pump from the system.  The drawing does not show a shut-off valve between the tank and this coupler but one should be included.  This diagram is representational only and is not intended to show the complete plumbing required as each system needs will vary.  Plumbing arrangement has been changed from elevation to plan view to show the pumps and skimmers easier with out obstructing other details.
Shut-off valve.  This can also be used to regulate the water flow.
Flexible 1/2" ID reinforced vinyl tubing to the main tank  Hose in connected to PVC reducer and held in place with a hose clamp.  Note:  Use only flexible reinforced hose, do not use standard vinyl tubing as vinyl tubing will likely NOT withstand the pressure over an extended period of time.  Flexible hose also reduces the number of 90 degree connections encountered which can restrict flow.
Plenum system.  The main support consist of 1/2" eggcrate material.  This eggcrate is supported by 1/2" x 1" strips of Sintra (an extruded PVC sheet stock) on edge.  The strips do not extend the full width but are short strips staggered to prevent forming sealed pockets.  This strips are bonded to the bottom glass using silicon to prevent their moving during installation.  Note:  1" OD PVC tubing can also be used to create the the eggcrate spacer / supports
Plastic window screen mesh.  This mesh is laid directly on top of the eggcrate grid to prevent the base layer material from falling through the grid.  Be sure to get a tight fit and not allow any gaps that will allow material to penetrate.  This same mesh is applied over the top of the base layer to separate the base layer and the Oolitic sand layer.
Base layer of substrate, approximately 1.2" deep.  This can be crushed coral.
Middle layer of substrate, approximately 1.2 - 1.8" deep.  This layer consist of Oolitic sand. (Remember the mesh layer over the crushed coral before the Oolitic sand).
Live Sand, approximately 1.2" deep.  This layer should be well stocked.


Fiji live rock, approximately 45 pounds.
Macro algae.
Water flow path.  This indicates the flow of water from the overflow located in the main tank (in my case this is located upstairs)  The water flows down through the biomass, under the baffle and then over the first overflow baffle.  Inside the main tank / refugium area, powerheads provide additional circulation.  The water flows over the end baffle into the outlet reserve where the circulation pump returns the water to the main tank.  The protein skimmer can also use the outlet reserve to receive and return water to the sump.
Protein Skimmer.  Connected to 1/2" bulkheads installed in the end of the tank.
Submersible powerhead.  The Red Sea Berlin Turbo XL uses a RIO 2500 powerhead with a custom impeller designed especially for this skimmer.


The sump tank includes a full hood with standard twin-tube fluorescent lighting.  This lighting is set on timers for a reverse lighting schedule.  In the evening at about the same time when the main tank lighting goes off the sump lighting turns on and turns off in the morning when the main tank lighting comes back on.  The purpose of this reversed lighting schedule is to help off-set the changes in PH that occur in the main tank during the day/night cycle.

The refugium area can be stocked with breeding shrimp and other critters that would normally be prayed upon in the main tank.  Unfortunately in my case the location of the tank requires the use of a circulating pump to return the water to the tank.  The use of a pump is detrimental to most of the beneficial xxxxx produced by the reproduction process in the refugium.

The macro algae growth helps to convert Nitrates from the water to xxxxxx.  This can also serve as a growing area for harvesting fresh algae to feed to the herbivores in the main tank.

The water surface in the sump area is held down approximately 3" from the top to allow additional room in the tank to prevent overflows.  In the event that there is a power failure, etc and the water in the two hoses drains back into the sump it is important to allow enough tank space to accommodate this additional water.