|The Krib Plants Plant People George Booth||[E-mail]|
One thing about a large glass tank - they sure are heavy compared to an acrylic tank! We were also surprised at the amount of distortion the thick glass causes. Acrylic has an index of refraction close to that of water and the acrylic is thinner, making for very little optical distortion. A plus for the glass tank is the fact that the sides and back provide more of a "mirror" effect than the acrylic tanks. When we look in from the top, the sides and back reflect the plants, giving an impression of a much larger tank.
The stand is a simple commercial unit made by Oceanic. It was stained a medium dull brown which we darkened to match the woodwork around it. We also gave it a coat of satin polyurethane to impart a more finished look and protect it from water splashes.
Besides refinishing the stand, we removed a center brace in the front between the doors. The doors are each only 1 foot wide and with the center brace, access to the cabinet was severely restricted. We wanted the trickle filter to be inside the cabinet and the center brace made it impossible to remove for cleaning. The brace was glued to one of the doors to prevent a gap. By the way, newer versions of the cabinet are built this way.
The stand is of basic 2x4 construction with an open top and bottom. The open top is nice because we can see the bottom of the tank and can monitor root growth. We cut some 3/4" plywood to fit in the open bottom to provide a large flush area for the equipment. The plywood is covered with wood-grain Contact shelf paper to match the cabinet.
The tank and stand are postioned about 12" away from the wall, next to a planter box. A plant shelf is positioned between the tank and the wall, about 6" below the tank top. This allows us to have small plants behind the tank and larger plants beside the tank in the planter box.
We had at first thought about using the planter box as an indoor pond and trickle filter sump. The idea was to put water hyacinth in the pond to take care of nitrates and reduce the need for water changes. After some thought, we became concerned about heat loss, evaporation and excess CO2 usage. We also were afraid the water hyacinth might outcompete the other aquatic plants for nutrients. We still might make a small pond in the planter box, but keep it separate from the SST.
The SST is protected by a Ground Fault Interrupter (GFI). We replaced the normal electrical receptacle by the tank with a Leviton unit that protects both sockets. A plug-in surge protector goes between one of the sockets and the electronic equipment in the tank. The tank lighting is plugged into the other socket.
Two quad wall outlets are mounted inside the cabinet provide power for the various accessories. One of the quad outlets is controlled by a on-off switch mounted on a "control panel" in the cabinet. Items which are turned off for maintenace are connected to this outlet. The other outlet is on all the time. Both of the outlet sets are protected by the GFI and surge protector.
A second on-off switch is connected to a flourescent strip light to provide illumination in the cabinet. The light has proven to be an excellent idea, allowing us to easily work in the cabinet without using a flashlight or dragging an external light around. We plan to retrofit lights to our other aquarium cabinets.
The control panel also has a power strip mounted in it, giving us a convenient place to plug in the dual light timers. The power strip is plugged directly into the GFI protected wall outlet.
After working with the new tank for a few days, we have decided that the "control panel" is actually a necessity, not a luxury. Being able to simply turn off the filter with a switch and having light when and where we need it makes us wonder why we didn't do it before. (If Karla knew how much fun it is working with 14 ga. solid wire, she would realize why we haven't done it before!)
This is our first personal experience with MH lighting and we are very impressed, to say the least. The 5500K bulbs provide a very white light and the Agro-Lites add a reddish cast that is very pleasing. The MH lights come on at 12 noon and go off at 8 pm (at least until the plants are established). The flourescent lights come on at 4 pm and go off at 10 pm, providing a sunset-like effect with their reddish light. Since the MH lights take about 5 minutes to reach full brillance, we are not concerned about simulating a sunrise.
The design of the Hamilton unit seems very well done. The ballasts for both sets of lights are contained in a remote box with about 10 feet of cord and connectors between the hood and ballasts. Each set of lights has a separate power cord, allowing separate timers. A fan is in the hood and just runs when the MH lights are on. An acrylic plate goes across the bottom to protect from water splashes. We were surprised that the MH ballast is almost silent (we had seen cheaper units in hydroponics stores that hummed very loudly).
The only work we had to do with the lights was to drill two holes in the top and mount some hooks with which to hang the hood. Some swag hooks with toggle bolts were mounted in the ceiling above the tank and the hood is suspended via decorative chain. The hood is very light, so strength in the mounting hardware is not required. The ballast sits on the floor behind the tank (it weighs about 30 pounds).
We still have to paint the hood since it comes in basic black and our walls are off-white. With the fan, the hood barely gets warm to the touch so any kind of paint will do. We also need to get some vinyl paint to paint the cables that go from the light to the ballast since they come in a lovely bright red!
We selected the 250 watt heating coils offered by Dupla even though this is more than they recommend for a tank of this size. We justified our decision by noting that the tank will be warmer than the Dupla recommendation (82 degress versus 76 degress), the house is kept fairly cool in the winter (68 degrees), the top will be open, and glass is a poor insulator compared to acrylic. 250 watts seems appropriate since we use 2 100 watt heaters in the AOA.
What we didn't understand was that the cable rating seems to more based on the bottom area of a specific tank size than the amount of heat needed. When we installed the cables, we found that the cable was too long for the tank if we used the spacing dictated by the Dupla cable anchors. We solved the problem by turning the spacers at a 45 degree angle, causing the spacing to be less than standard. This also has the benefit of locking the cables tightly into the anchors, giving us more control when we arranged the cable (it has a pretty good "set" because it comes tightly coiled when it is packed and it doesn't like to lay straight). We feel that, within limits, the spacing is not critical to the operation of the coils. The pictures in "The Optimum Aquarium" show a much tighter spacing than we are using and there is nothing in the instructions that say otherwise.
The heating cable is secured to the bottom with 42 Dupla cable anchors. This is slightly less than recommended (they are spaced 8" apart rather than 6"). It is not clear why so many anchors are needed, since the gravel will do a pretty good job of keeping it in place. The only obvious thing is to prevent the cable from moving when plants are uprooted in case the plant roots get tangled in the cable. Since the cables are within 1/8" of the tank bottom and they are coated with a very slippery silicon rubber, we aren't very concerned about this.
The heating coils are driven by a 250 watt Duplamat stepdown transformer operating at 24 volts. The low cable voltage provides a safety factor in case the cable sheath is nicked or broken accidently. The Duplamat plugs into a special plug provided on the DuplaTherm controller.
The DuplaTherm Digital controller is a nicely designed unit with two temperature sensors, one for control and an independent sensor for the digital display. Having a separate display sensor allows one to move the sensor around the tank to make sure there are no hot or cold spots. The one inconvenient factor is the special 110 volt AC plug used on the unit. It is designed for German receptacles and requires an adaptor from Radio Shack. A normal U.S. style plug can't be put on the power cable because the plug also controls the DuplaMat transformer. We had to drill a 1 1/2" hole in the back of the cabinet to support the German plug and then connected the Radio Shack adaptor to it.
The controller currently maintains the temperature at 80 degress F +/- 0.1 degree. Once the plants have acclimated and we remove the "seed" fish, we will raise it to 82 degrees for the discus.
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