There’s an old saying that the cobbler’s children have no shoes. Sometimes we feel that way because we stay busy designing things for other people or for demos that we don’t have time to just build something we want. [Blue Blade Fish] wanted to build an Arduino-based aquarium controller. He’s detailed the system in (so far) 14 videos and it looks solid.

This isn’t just a simple controller, either. It is a modular design with an Arduino Mega and a lot of I/O for a serious fish tank. There are controls for heaters, fans, lights, wave makers and even top-off valves. The system can simulate moonlight at night and has an LCD display and keys. There’s also an Ethernet port and a Raspberry Pi component that creates a web interface, data storage, and configures the system. Even fail safes have been designed into the system, so you don’t boil or freeze expensive fishes. No wonder it took 14 videos!

We really liked the moonlight which has 32 LEDs with custom switching and a shift register. In front of the LEDs is — surprise — a picture of the moon. We wondered how it would be with a 3D-printed lilthophane which might diffuse the LEDs more. Because of the shift register, it is simple to control all the lights with just a few pins.

Apparently, giving fish an idea of the ambient lighting outside is important to people who keep fish. Because of the safeguards, a bad software bug isn’t going to boil his fish. Despite the looks, apparently neither will this upcycled fish tank.

[Helios Labs] recently published version two of their 3D printed fish feeder. The system is designed to feed their fish twice a day. The design consists of nine separate STL files and can be mounted to a planter hanging above a fish tank in an aquaponics system. It probably wouldn’t take much to modify the design to work with a regular fish tank, though.

The system is very simple. The unit is primarily a box, or hopper, that holds the fish food. Towards the bottom is a 3D printed auger. The auger is super glued to the gear of a servo. The 9g servo is small and comes with internal limiters that only allow it to rotate about 180 degrees. The servo must be opened up and the limiters must be removed in order to enable a full 360 degree rotation. The servo is controlled by an Arduino, which can be mounted directly to the 3D printed case. The auger is designed in such a way as to prevent the fish food from accidentally entering the electronics compartment.

You might think that this project would use a real-time clock chip, or possibly interface with a computer to keep the time. Instead, the code simply feeds the fish one time as soon as it’s plugged in. Then it uses the “delay” function in order to wait a set period of time before feeding the fish a second time. In the example code this is set to 28,800,000 milliseconds, or eight hours. After feeding the fish a second time, the delay function is called again in order to wait until the original starting time.