Tank:
 

My reef tank is set up in a Jewel 48 inch (120cm) tank which takes about 55 imperial gallons (about 275 litres). Not the cheapest tank in the world but the curved front makes it a very impressive piece of furniture. The standard tank as delivered comes with a filter box glued into the corner, a 200W heater and 2 basic fluorescent tubes. This may be a serviceable "all in one" solution for a cold water aquarium but is no where near appropriate for a reef tank. Hence I made quite a few upgrades. The first change I made was to remove the filter box which took up a lot of room in the tank. The plinth that comes with the tank has two cupboards with very useful rear cut outs to allow all of the filtering equipment to be kept tidy but accessible.
 

Electrics:
 

First of all, given the large number of electrical devices that I planned to use in and around the tank I thought it worthwhile to invest in a decent power set up. I lined the insides of the cupboards with chipboard so that I could fix equipment inside the cupboards without drilling holes in the furniture. Each cupboard has 6 individually switched power points, running on separate RCCB (Residual Current Circuit Breaker) circuits. A custom built switch box allows me to control each device individually. You can see the two RCCB units and master power switch in the right hand cupboard. I chose to install dual RCCB circuits so that, by carefully choosing which devices are attached to each circuit I can ensure that at least part of the tank system would stay functional in the event of one RCCB tripping.
 

Filters:
 

The filter set up is shown schematically as follows:

I have a Fluval 403 canister which pumps water around the filter system. The Fluval contains physical filter sponges, activated carbon (sometimes), phosphate absorber, some nitrate remover and some ceramic chips for biological filtering. The ceramic chips are there as a backup to the fluidised bed which provides the bulk of the aerobic bacterial filtration in the system.

Part of the outflow from the canister filter is routed into a Lifeguard fluidised bed (the fluidised bed needs a relatively slow flow of water so most of the flow from the canister is not fed through this). The fluidised bed provides excellent aerobic biological filtration - once it was established I have never seen any measurable Ammonia or Nitrite in the tank, even after the introduction of new livestock. I have found that it is important to run the fluidised bed significantly below the marked "maximum fluid level" to avoid the system blowing the media into the tank - this does not seem to affect the performance.

The water which is not routed through the fluidised bed is passed through a "no name" U.V. steriliser. I am not sure if it is better to place the U.V. in the relatively low pressure path of the fluidised bed or in the main outflow from the canister filter.

The outflow of the fluidised bed is taken up above the tank to a home made (somewhat experimental) coil denitrator. The denitrator requires a VERY low flow rate so most of the water passing into the reservoir flows straight through and back into the tank. Water is dripped into the coil denitrator very slowly where, theoretically at least, it goes anaerobic and allows nitrate consuming bacteria to thrive. You can read more about the coil denitrator here.

I also have a large protein skimmer in the tank which is driven from an air pump located in one of the cupboards.
 

Plumbing:
 

All of the filter equipment is packed into the two cupboards below the tank. I have built trays in the bottom of each cupboard out of acrylic sheet, Araldite and tank sealer to catch any water leakage which might occur during cleaning and maintenance. As I am paranoid about leaks I have also sealed every hose connection with tank sealer even though each has either a high quality Fluval screw joint or a jubilee clip.

As you can see from the picture I have fitted Fluval double quick release taps to every joint on every piece of the filter equipment. Given the cramped conditions inside the cupboards it is very Important to be able to remove each unit for cleaning and maintenance so these taps are indispensable.

I also have "pump in" and pump out" taps fitted in the left hand cupboard - the "pump out" tap is connected to a small power head in the tank which is used to flush water out during a water change. The "pump in" tap is just a dry riser into the tank - when I do water changes I drop a small power head into my tub of clean water and connect it to the "pump in" tap. Water changes are boring but necessary so I wanted to make the process as painless as possible.
 

Water Movement:
 

To create water movement in the tank I have two 1100 litre/hour power heads, one at each corner of the tank pushing water up and towards the centre of the tank. This creates a lot of currents around the rock work which the fish like and helps to keep food suspended in the water. I also have another 1100 litre/hour powerhead located at the back of the tank pushing water forward through a spray bar which runs along the bottom of the tank at the back. This creates water movement in the quite corners of the tank and helps to push food and detritus forward so that it does not get a chance to pile up and decompose at the back of the tank.
 

Heating:
 

Heat is provided by a 200W heater stuck to the back of the tank, heavily concealed by rock to ensure that anemones cannot sit on the heater and burn themselves. So far I have no backup heating system, nor do I have any fail-safe thermostat to cut out the heater should it get stuck in the on position - some room for improvement there. The fluorescent tubes also provide a significant amount of heat to the tank during the day. I used to think that there was no chance of the the tank overheating but recently I have noticed that on hot days the temperature can rise to over 80 degrees. Maybe I will have to invest in some cooling technology soon.
 

Air:
 

Apart from the air pump which operates the protein skimmer I also have a second pump to provide general water aeration. It feeds air via adjustable taps to the inlets of the two main water movement power heads and to air-stones and an air-stone bar at the back of the tank. I used to just pump air through the power heads which created excellent aeration but seems to disturb the fish and made the whole tank more difficult to view so I tend to just use the air-stones now.
 

Lighting:
 

I have 3 fluorescent tubes lighting the tank - 2 are mounted on the fittings supplied with the tank and one extra I added myself. Each tube is powered separately and they are all connected via timers which provide daylight, dawn and dusk by switching the tubes on and off one by one in the morning and evening. The following tubes are fitted:

Triton 2 daylight.
Marineglow actinic.
Powerglow daylight.

Rock & Sand:
 

The tank has a layer of coarse sand on the bottom about 1.5cm thick, on top of that is about 1.5cm of crushed coral. I have tried to keep the substrate as thin as possible so as not to use up water volume and even considered a completely bare base. However, the sand substrate helps to seat the rocks and the crushed coral should contribute to overall calcium levels. I have built a large reef wall from a mixture of tufa rock and live rock. I have tried to keep the structure as open as possible so that there are a lot of caves and crevices. Where possible I have avoided putting rocks at the base of the structure which have big "footprint" hence there is very little rock actually touching the base. This helps to keep the water flow around the base high, avoids detritus piling up and helps to avoid anaerobic areas forming in the sand. I have built overhangs so that there are some shady parts of the tank species who do not like bright light. Smaller rocks have been used to conceal the power heads.
 

Other Stuff:
 

The tank also contains a brine shrimp hatcher attached to one of the air pumps. I regularly hatch about half a teaspoon of brine shrimp eggs and drop them into the tank as supplemental food for the corals & small fish. It is important to shut off the main filter pumps when the shrimps are introduced or they tend to get sucked into the filter too quickly.