Aquarium water level sensor for $2!!

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UPGRADED Water level alarm ►

Do you guys remember the video we did on the “water alarm”?
We essentially took a $5 smoke detector, and connected some wires to it to create a loud water alarm that could be used to sense water.
Well, i have a small upgrade that you can add to it for only $2 more.
The previous sensor only sensed when water was present. Whether it was a spill or when your tank was down filling.
However, there are still some uses we can get out of this.
If you did not watch the original video, i highly suggest you do or this video will not make any sense for you.
The addition we want to make is a simple float switch.
I got one on ebay for under $2 with free shipping.
The way these work are simple. The float switch is used to open and close connections by use of a buoyant plastic nut on the switch. Depending on the orientation of this switch, it will either close or open a circuit. So we can use it to turn the alarm on if the water level rises, or turn the switch around and we can now use it to sound the alarm if the water level drops.
This can connect to the preexisting alarm we created in the previous video by simply attaching the wires. Which wires connect will not matter.
Now we can install the float switch in the tank using a simple airline suction cup.
Again, depending on how you have this set up, it will now sound if the water level rises or drops. Which can be useful for many applications in your hobby. If we have the plastic nut upright, it will sound if the nut rises due to water level. If we install the nut upside down, the alarm will then sound if the water level drops.


The king of DIY


What do you think?


Written by The king of DIY

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  1. Awesome idea and an affordable safety feature… I'm sure every reefer at some point has turned on the RO unit and then forgotten about it only to be greeted with wet feet! 😀
    You only make that mistake once and then fit a float valve. But this extra measure would certainly give more peace of mind and I would say possibly a marriage saver. Lol

    Good job as always Joey… Thumbs up…




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