A Hole in the Wall Reef Tank

My wife and I had been looking for a new house last year and one of the considerations of the new house was to be able fit a 6 to 8 foot reef tank into a lounge or dining room. I had already been running a 4 foot reef tank for a year in our previous home and had learnt a lot in this time mainly from internet forums and books.
One of our main concerns was the noise created from all the pumps, the overspill from the lighting into the room and the inevitable salt water spills on the carpet that we all get from water changes and general maintenance.
So when we found this house which had an integral garage which the lounge backed onto, we both realised that a hole in the wall tank would not only overcome all these problems, but would also free up a lot of room in the lounge.

We moved into the new house in February 2006 and a week later we started the ball rolling to build my dream tank.
First on the list was to get a builder round whom we already knew and to give us a quote on knocking out a 6 foot by 2 1/2 foot hole in the lounge wall and to discuss issues such as building regulations.
After a quick phone call to the local council planning department we were given the go ahead, although with a couple of constraints.
As the lounge and garage would effectively become one room once a hole was knocked through, we had to think about the risk of a fire starting in the garage and spreading to the lounge.
We had two choices, make the fish tank out of fire retardant glass and seal around the outside with a special fire resistant mastic, or build a 30 minute fire retardant wall behind the fish tank separating it from the garage.
I phoned the company who were to be making the fish tank and enquired about making it out of fire retardant glass, this was a non-starter, it would have cost a fortune.
So we opted for the fire wall behind the tank, not only was this a lot cheaper but it has created a "tank room" separate from the garage and so it should stop all my tools and bicycles in the garage going rusty in 6 months!

A week later the hole had been knocked out and the stand built. The stand was constructed from up-turned concrete blocks with 3 reinforced concrete lintels across the top.
Because there is an access door into the garage from under the stairs, we had to allow for this and so the stand and tank were to be angled at 45 degrees at this end.

Next job was to create a level base for the tank to sit on. A sheet of 18mm MDF board cemented to the stand and a sheet of 2inch thick polystyrene did just the job. The plastering work was then finished off on the lounge side and it was now time to get the tank ordered up to size. I allowed a gap of 2cm all the way around the tank, just to be on the safe side that it would actually fit in the hole once delivered!
And now much to my wife's delight, we could now start decorating the lounge!

Next job was to think about the lighting and electrics. Luckily my wife's nephew is a qualified electrician. He installed a new consumer unit in the garage and a new circuit for the tank electrics, which were connected to an RCBO on the consumer unit, this meant that if a fuse were to blow anywhere else in the house it wouldn't trip out the fish tank electrics and in the event of a power cut the fish tank would start up again on its own. A plug board was made up with 12 double sockets and a further 3 double sockets for the lighting above the tank.
I opted for 3 x 250 watt Coralvue metal halide pendants and ballasts for the main lighting with 2 x 4 foot T5 actincs.

The tank was to be 6 ft x 2 1/2ft x 2ft (L,H,W) made from 12mm glass with a double base. With holes drilled for 2 closed loop circulation pumps, sump return pump and 2 overflows with a weir. Along with a custom made sump tank to fit underneath.
I arranged for 4 people to be there when the tank was delivered to carry it off the lorry onto the stand - with hind sight I should have had a few more as we were close to dropping half a ton of glass in my driveway!

The tank safely in place it was time to start the plumbing. Now I'd never done any plumbing before and it was a bit daunting, after a few chats on the internet I had got my head around it and started about cutting and gluing what seemed like a lot of pipe!

Two days later I had impressed myself with my handy-work and test filled the tank with tap water to see if it had any leaks. Well all 3 pumps and the skimmer were leaking! A few more cuts with the hacksaw and some more glue and this time everything was running smoothly.

I then started about filling the tank with RO water. This took a couple of days and around 750 litres. The pumps and streams were fired up and the heaters turned on and the salt added to bring the water up to a specific gravity of 1.025.
A shallow bed of aragonite sand was added and 2 egg crate racks I had knocked up were placed on the bottom for the liverock to sit on.
I had calculated I needed about 100kg of liverock, I already had 40kg in my current tank which had been set up in the garage since we moved in. So a round trip of 300 miles to STM got me the other 60kg I needed.

I then had to dig out my carpenters skills from within, and build a frame for the lounge side of the tank to make it nice and tidy. Firstly I siliconed around the entire tank so there were no air gaps through to the garage. After searching all the local DIY stores I found some nice fat door frame architrave which would do the job nicely. Out came the mitre saw, tape measure and a couple of tubes of "no more nails" I'd created a pleasing finish.
All this was done just in time before we were due to go away on holiday, so when we arrived back I was hoping any ammonia spikes from die-off on the rocks had gone and the tank would be ready for stocking.

On return from holiday, things didn't go quite as planned. The auto top-up had run out and so the water level in the sump tank had dropped below the level of the return pump, so no water was being circulated through the system to the skimmer and phosphate reactor, this resulted in a mass of hair algae in the display tank, as you can imagine I was not best pleased!
So, a bit of a set back but nothing major, all new tanks go through algae outbreaks, so it was time to get some clean up crew in there as soon as possible. Half a dozen blue legged hermits, 30 turbo snails and 1 week had effects on the hair algae far beyond what I had envisaged - it was pretty much all gone!
So the time had come to transfer my existing tank inhabitants to the new tank. This was done over a few days, the liverock first, followed by the corals and finally the fish.

Now that the old tank had been moved out of the way, we could get the fire resistant wall put up behind the tank. This consisted of a stud partition, plaster boarded on both sides and filled in the middle with a fire resistant wall insulation, and a fire door giving access to the garage. The wall was skimmed over and painted up in a nice sea blue emulsion. Finally bathroom extractor fans were fitted to the wall and ducted to outside through the garage, one bringing fresh air in, the other taking the humid air out.

Finally I can sit back and enjoy my tank and watch it grow. Both myself and wife are very pleased with the way it all turned out. And in case you are wondering if it satisfied our initial concerns, yes it did! You can hardly hear any noise at all from the tank when sat in the lounge. I still spill water on the floor from time to time, but this is longer a problem, the tank room has a bare concrete floor and a mop and bucket does the job and no damaged carpets! We don't get lighting overspill anymore, the lights in the tank do light up the lounge a bit, but this is filtered through the water and not directly hitting us in the eyes like with our old tank!

Livestock click on these links for a list of my fish and inverts

Parameters follow this link to see my water parameters

Circulation is supplied by 2 x Tunze Turbelle 6100 Streams connected to a 7094 controller running 24/7.
Also I have 2 closed loops powered by Ocean Runner 3500 pumps, the pumps feed 2 25mm spray bars, one at the front and one at the back of the tank, both stretching the full length pointing upwards to keep any detrius in suspension so that it is taken over the weir and into the skimmer and sump.
The sump to tank return flow is powered by a Ocean Runner 6500 pump.

Total water turnover in the display tank is approximately 34,000 litres per hour or 52 x main tank volume.

Lighting is run by 2 x 54watt Giesemann D&D T5 Pure Actinics, 3 x 250 watt 14k MarineLux metal halide bulbs and 2 Moonlight LED's run on a lunar tracker which are on at night. Sump is lit by a 11watt clip on lamp, the refugium is lit by an Interpet 55w twin power compact T5 lamp and the Nano Tank is lit by a Dupla Electra 150w metal halide with 14k MarineLux bulb..

Display Tank Lighting period:
11.00 - Actinics and sump light ON.
12.00 - 1st Halide ON
12.30 - 2nd Halide ON
13.00 - 3rd Halide ON
21.00 - 1st Halide OFF
21.30 - 2nd Halide OFF
22.00 - 3rd Halide OFF
22.30 - Moonlight LED's ON
23.00 - Actinics OFF
08.00 - Moonlight LED's OFF

Nano Tank Lighting Period:
13.00 - ON
21.00 - OFF

Refugium Lighting Period:
22.00 - ON
12.00 (noon) - OFF

Filtration is by 100kg of premium grade Fiji Liverock sat on eggcrate in the display tank. Water flows out of the display tank via the weir into 2 overflows, I have a Deltec AP701 Skimmer which takes about 50% of the water that goes over the weir, the rest goes to the main sump which contains the heaters, ZeoLith filter, phosphate reactor, pump to UV light and a bag of activated carbon.

The return pump splits in 2, 70% going back to the main tank, 30% going to a DSB tank which is 6 inches deep of aragonite sand, the end chamber of this tank is half filled with 5 kg of live rock, the DSB is kept totally in the dark to eliminate algae growth and also works as a cryptic zone which promotes the ammount of detrius eating and water filtering bacteria and critters. The water flows out of the Cryptic zone into a Nano Tank below which has another 15kg of liverock and 2inches of aragonite sand. This then overflows back to the main sump.

Above the DSB tank is a refugium, fed 1000 l/h by a maxijet 1200 pump in the weir of the tank. The refugium contains 2 inches of coral sand, some live rock rubble and lots of macro algae - Chaeto, Caluerpa, Halimeda and some mangroves. The water falls out of the fuge tank via gravity and back into the display tank. This should help keep the tank fed with live pods and other critters and the algae in there helps reduce nitrate and phosphate levels as well as keep the PH elevated.
I have added a Korallin Sulphur De-Nitrator reactor which is Teed off from the pump feeding the phosphate reactor and UV light, it is currently on 1 drip per second.

I have also recently started the Fauna Marin UNLS (ultra low nutrient system) which incorporates a modified EHEIM canister filter filled with ZeoLites, this is sat in the main sump and feeds off of the chiller pump. I also add daily Fauna Marin UltraBAK, UltraMinS and occasionally add UltraBio bacteria.

Water Top Up is controlled by a System 2000 water level controller sited in the sump which is on 24/7. I have a 60litre container holding RO water (supplied by a RO Man 100gall/day 6 stage RO system) the water is drip fed via a peri pump at a rate of about 2 drops per second to the main sump.
The 60 litre RO container is filled about every 5 days, so my evaporation rate is about 70litres per week.

Heating is controlled by a System 2000, 700watt temperature controller with 2 x 300 watt heaters sited in the sump tank. Although the heaters rarely come on.

Cooling & Air Exchange is controlled by 2 bathroom air extraction fans in the wall in the tank room. 1 of these fans pulls in fresh air from outside, the other extracts air from the tank room to help with humidity levels. I also have 2 clip on fans above the main tank, 1 on the sump and 1 on the nano tank. All 6 fans run 24/7. I have also added a Teco TR20 Chiller which helps control the temperature further in the summer. The temperature over a 24 hour period is rarely outside of 26c and 26.3c.

Maintenance: I make monthly water changes of 60 litres, which is approximately 8% of the systems volume. I use Reef Crystals as I find it has a good level of calcium and magnesium and mixes to a PH of above 8.40. For the water changes I use my top up reservoir, fill with RO water, salt to specific gravity of 1.026 and heat and circulate for 24 hours. After which time I will check the SG with a refractometer, check the PH is above 8.0 and it is heated to the same temperature as the tank water. Once this is all fine, I simply turn off the stream pumps in the tank, turn off the return pump from the sump tank and then syphon out 60 litres using a 40mm flexi hose and a 25 litre water container, then pump the new water into the sump using a maxi-jet 1200 powerhead, while this is pumping in I turn back on the sump to tank return pump and turn the streams back on once the level in the tank is back to the top. The whole water change process takes under 10 minutes.

Activated carbon is renewed about twice a month and phosphate remover is changed once I notice phosphate levels increasing, usually about every 3 to 4 weeks.
Zeolites are changed at a rate of 25% every 6 weeks.

I clean the glass on the display tank every day with a couple of mag-floats and scrape off any stubborn algae and coraline once a week with a razor blade scraper.

Water Tests: I carry out water tests every 7 to 10 days.
I use Salifert test kits for Calcium, Magnesium, Alkalinity, Nitrate, Nitrite and Ammonia. Phosphate is tested for with the D+D Deltec High Sensitivity Phosphate Test kit, SG and Salinity is tested with a refractometer, PH with a Pinpoint PH monitor, ORP with an Aqua Digital Redox Controller,  Temperature with a System 2000 Temperature Control Module and Potassium with the Fauna Marin Kalium test kit. I also have Salifert Strontium and Iodine test kits, but do not test these very often.

Additives: I run a Grotech Calcium reactor containing coral gravel/skeletons this replenishes calcium, alkalinity and magnesium amongst other trace elements. I also add a few drops of Iodine supplement every week and feed the tank coral vibrance coral food now and again. Im also adding 3ml of UltraBAK daily and 1ml of UltraMinS daily.

Costings: I get a lot of emails from people thinking about doing a similar project and the question that comes up the most is "How did it all cost?"
So I have decided to give an approximate price breakdown. All prices quoted below are taken from various web sites I have used, some of the equipment I have was bought secondhand from E-Bay or other reefers, but I have given the NEW prices below for everything I own.

You could replicate my system for a lot less, you wouldn't have to have the sump stack for example. If you weren't planning on keeping so many stony corals then you wouldn't necessarily need the calcium reactor and kalkwasser stirrer. You wouldn't have to have the de-nitrator. You could go for a cheaper lighting option like T5 tubes. You could also run without the chiller. So you can see you could do it all for at least £1500 less probably a bit more. Whatever your budget, allow at least 20% over!

If you want to see many more photos and all the trials and tribulations of the tank build from start to present, then click here to follow all the action.

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