With all of the money we have invested in critters I decided it was time to buy some insurance in the form of a battery backup system. I have been running a Penn-Plax Silent Air B11 which will aerate the tank for up to 72 hours on a single pair of D-cells. But I wanted something more flexible...
Here is a good article on battery backup systems...
http://reefkeeping.com/issues/2006-05/gh/index.php
Generators offer long term power but, aside from very expensive permanent installations they are not uninteruptable in the sense that someone must turn them on. So I decided on a system with a power inverter, built-in battery charger, and automatic switching when ac power is interupted paired with a deep-cycle marine battery.
The Tripp-Lite APS612 and APS750 seem to be the most popular units used among aquarium keepers. But there is a new unit the APS700HF
http://tripplite.com/products/produc...productID=3298 which offers everything I need in a compact design. It can supply up to 700W of continuous power. Since i only plan to run a few powerheads with this system it will have more than enough power-and in a pinch could run my entire system including heater (less the lighting) for a shorter duration.
The build is really not very difficult. Here are the parts you would need:
-APS700HF Power Inverter/Charger ~$160
-DieHard Marine Deep Cycle Battery or any comparable battery tax ~$70
-2x 4 gauge battery cables ~24-30" wire length ~$10
-x # feet of 8 gauge ground wire (long enough to reach from inverter to water pipe) ~$5
-grounding clamp ~$2-3
-marine battery box ~$10
total ~$275 after taxes
Tools: something to cut and strip wire, allen wrenches for securing wiring in inverter terminals, straight-edge screwdriver
The inverter has a power-in cord, and power-out, as well as positive and negative terminals to connect to the battery. There is also a ground terminal on the inverter housing.
After preparing and labeling the battery cables as positive and negative they were connected to the inverter/charger.
The ground wire was secured to the inverter/charger and the other end clamped to the nearest water pipe.
Battery cables were attached to the appropriate battery terminals, the marine battery box was closed up, and the inverter/charger was secured to the battery box.
After the unit was situated next to my tank a maxijet 900 was plugged into the power-out cord and the inverter/charger was finally plugged in. When ac power is connected the powerhead is run off of ac, in the event of an outage the inverter uses the battery's 12V DC to run the pump. I later unplugged the inverter/charger and am currently testing the system to see how long it will run the maxijet. There is a low battery alarm built into inverter to protect the battery from being irreversibly discharged. The maxijet is running perfectly-quiet-in spite of the "modified sine wave" the inverter produces. I anticipate >24 hours of run-time with the single maxijet. I will try to come up with the calculations. Eventually this will run Tunze nanostreams. Roger Vitko of Tunze USA has stated that Tunze pumps run just fine off of the modified sine wave and since the electronic versions are DC they are well suited to use on a modified sine wave power supply (since the Tunze transformer knocks it down to DC anyways).
If this saves a loved critters life-awesome-if not it offers some piece of mind. Let me know if you have any questions. Thought this might be a good little instructive piece.
TG
