There are a number of things that should be considered when planning a reef tank. With the amount of money invested in our aquarium, we need to carefully plan and design our systems to prevent aquarium disasters.
1. Electricity
When planning a tank. It is a good idea to use more than one electrical circuit. You may have some restrictions, like living in an apartment, but whenever possible you need to consider it. In either case you want to think of the worst possible scenario and make sure you have an action plan. If you only have one circuit and it was to trip unexpectedly all of your circulation devices will shut off. Gone unnoticed while away from the house, could be disastrous in as little as a few hours. If you have multiple circuits, it is best to place at least one circulation device on each circuit. That way if one circuit trips there is at least some circulation in the fish tank.
2. Overflows
When you have time to plan your aquarium, it is advisable to purchase a reef ready tank. While siphon overflows can work flawlessly for years, it only takes one failure to become a catastrophe. Some hobbyists claim that having a tank drilled or purchasing a drilled tank is too expense. But if the hang on back overflow were to fail, think of the damages it could cause to the floor and anything underneath the aquarium. Probably the biggest reason people use Hang on the Back Overflow Boxes is because they do not want to take the time or trouble of having their tank drilled.
With advances in circulation devices, it is no longer necessary to move large volumes of water through your overflow drains. The more you push your overflows, the greater the chance of failure. When using single overflows, a clog or partial clog can be disastrous. Not only can it ruin floors, walls, and ceilings, but it can also harm livestock. If you decide to use a single overflow be sure to use strainers on them to prevent large particles or snails from clogging them.
For redundancy, it is best to use more than one overflow. Optimally, each overflow should be large enough that if one was totally clogged, the other one could handle the full load. When using large return pumps this may not always be possible.
3. Circulation
There are many ways to provide flow in a reef tank. Powerheads, closed loops, and wave makers are popular circulation devices. There was a previous trend to use a large return pump and flow deflectors to provide all of the aquarium’s circulation. Most people used this method to keep powerheads and other bulky items out of the show tank for aesthetic reasons. From a redundancy stand point this is not a good solution. In the event of return pump failure, all of your circulation is now stopped.
It is always advisable to use more than one device for your circulation needs. That way if a pump failure occurs, you have at least some circulation for gas exchange. Ideally they should be arranged on different electrical circuits, so if one circuit were tripped, you would have at least some circulation in the tank. Sometimes powerheads and other more bulky devices are a necessary evil, and one must sacrifice aesthetics in an effort to prevent catastrophes.
4. Heaters
In most places, Heaters are a necessity. One of the leading heater malfunctions is the built in thermostat. Never trust the built in thermostat. They have been known to fail in the on position.
Some hobbyists think two smaller heaters are better than using one large heater. Since many aquarists push the upper temperatures with Metal Halide Lighting Systems and large pumps, even a small heater can produce enough heat to cook our fish tanks if stuck in the on position. Also, having two heaters doubles your risk of heater failure.
It is crucial to use an additional Temperature Controller with any heater to prevent a disaster. Typically you set the built in thermostat slightly above what the temperature controller is set to. For example, you would set the heater to 79 degrees and the temperature controller to 78 degrees. If for some reason the temperature controller malfunctions or is set incorrectly, the built in thermostat will turn it off.
Sometimes heater failure can cause current/voltage to leak in the tank. This is one of those areas where you should research the heater you plan to purchase. In the event of this type of failure, the outcome is not very pretty. In general, titanium will be a better option than a glass, but again nothing is guaranteed. You should consider using a GFCI circuit in conjunction with a ground probe. Remember that a ground probe is only useful when used with a GFCI circuit.
5. Lighting
Lighting is a key contributor to heat in modern reef tanks, usually most prevalent in the summer time. It is important to understand that when seasons change from winter to summer that heat can be a killer. This is probably the most common reason for tank crashes in the hobby.
A Chiller is probably one of the biggest equipment expenses for a saltwater aquarium. With thousands of dollars invested in your tank, it can be a wise purchase. However, there are other things short of a chiller that you can do. The use of fans is an affordable way to reduce heat put off from aquarium lighting. A temperature controller is a nice feature to be sure that fans are used only when necessary to minimize evaporation. Most controllers have features that can prevent your tank from overheating. You can set them so that if a certain temperature is reached, your lighting will automatically turn off. This is a great feature that can easily justify an aquarium. Outside of a heater your lighting is probably the second cause for overheating.
6. Top Off
Top off is probably one of the best automated addition for your aquarium setup, not only to reduce your daily maintenance, but to keep salinity as constant as possible. There are lots of top off solutions that can be achieved with virtually any budget. However, the most important factor is to have the worst case failure covered. There are three main types of top off. Float switch, gravity fed with float valve and dosing pumps. Special considerations also need to be in place if you use Kalkwasser to prevent the pH from getting too high.
Float switches are affordable and usually can be bought for under $20. However, they are prone to failing in the on position. To counter this worst case scenario, it is import to have a limited supply of top off water. The amount must be small enough that it would not overfill the sump and also to not significantly change the salinity. In general, about five to seven days of evaporated water is sufficient. You may also set your top off device on a timer or use a dosing pump that will only dispense “X” amount of water at any given time.
Using Kalkwasser with your top off water does have its advantages. However, you must be very careful to ensure that Kalkwasser is not overdosed or added too quickly. A dosing pump for Kalkwasser is highly recommended, provided that the tubing doesn’t become clogged with Kalkwasser.
7. Power Outages
Planning is important when it comes to power outages. While many of the solutions are not cheap, keep in mind your entire investment in livestock. For short power outages, your main focus should be oxygen levels. While temperature can also be an issue, it usually falls slowly and is usually not fatal.
When on a budget, Battery powered air pumps may be the best possible solution. There are some inexpensive ones powered by batteries. The downside is you have to be home when the power failure occurs to turn it on. If in a pinch an AC/DC Power Converter can be used along with a car or marine battery. The downside again is you have to be home to hook it up to your battery.
Typically Uninterruptible Power Supply (UPS) built for Computer will not run long enough to provide much power. However, they are relatively inexpensive and can run a small powerhead. One plus, is it should work without your presence. Some companies make a 500W inverter that you can hook several marine batteries up to. This is usually a good option for a 24 hour or less power outage and makes for a good first line of defense when you are at work, asleep, or when the tank is unattended. Depending on how many batteries you add, it may be possible to also add a heater. However this will greatly reduce the runtime.
A Power Generator is ideal for long power outages. The downside is that most portable generators require you to be home to hook them up. This is a good solution when used in conjunction with a UPS for those hours when you may not be at home.
8. Hardware Redundancy
Over time most equipment does fail. You should be prepared for such an occasion. All too often, you hear of people making a mad dash to find a replacement pump or light bulb. Have a replacement Return Pump available. Ideally it would be an identical pump, but an old pump can be used for backup until a new one can be purchased. In your plumbing design, it is advantageous to add unions and/or adapters so the pump can be easily swapped without making a mess.
9. Miscellaneous
Use plastic, not metal clamps on all barbed fittings. Make sure the sump has enough volume to handle the overflow in a power outage condition. You can drill a small hole just above the water line on the return to help stop the back siphon in a power outage.