Fish Tank Backup Pumps

Overview

This project is a work-in-progress.

The purpose of this project is to create a backup air and water pump system for my (Zack’s) fish tank.

Why Create a Backup?

Overtime, the water in an aquarium will become increasingly toxic. The main way to overcome this issue is to filter the water using biological and chemical processes. This is usually done through mechanical pumps. However, this can also be done by forcing water up through a filter medium using air pumps. If the main power goes out (such as a power outage), the normal filters are no longer functioning. The goal of this project is to create a simple, relatively cheap, automatic backup pump system.

Basically, I want to create a backup pump system in the case of a power outage. (Power outages are unfortunately pretty common in my current place of residence)

Requirements

Here’s my current requirements:

1. Run an air and mechanical pump off a single, common 5 volt USB power bank.
2. The air pump should be enough to run the main air network.
3. The mechanical water pump should be able to run the main HOB system
   1. NOTE: This ended up not working correctly (see below)
4. The resulting solution must be simple and mostly cost-efficient

Progress

1. Block Diagram / Circuit created – Completed
2. Supply List Created – Completed
3. Breadboard test – Completed
4. Soldered Project-board – Completed
5. Test – Completed (Got real-world results!)
6. Tweak and Fix any issues – In progress

Known Issues

1. The project board has a different hole spacing than the relays that I purchased. The current solution looks very bad and is not ideal.
2. The USB ports are not secured onto the board, this means they can come off easily
3. The Battery lead is fairly long (Maybe not fix)
4. The mechanical water pump did not work because the HOB filter starts siphoning through the pickup tube.

Planned Fixes

1. I will likely not fix the relay because it works and I would rather not break it.
2. The USB ports will be fixed by putting thick, double-sided tape under the ports.
3. The battery lead will not be fixed, it will be most-likely hung outside of the main controller
4. I have no fix planned for the mechanical water pump.

Future Feature Ideas

1. Attach a micro-controller (maybe Raspberry pi?) to send a text message on power outages.
   1. Automatically power off after warning to prevent power?
2. Design circuitry to detect pump faults
3. Design a nice-ish enclosure to put the electronics in.

Documentation

To be uploaded later.