DIY auto top off for cheap and easy

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Active member
Jan 13, 2004
I just completed an auto top off system that was super easy and cheap... thought I would share what and why I did it.

Why: My tank evaporates about 5 gallons per week, so I need to top off once a week at least. I am about to leave on vacation for 10 days and don't want to have to explaine to family and friends how to top off my tank without causing any problems.

What I did:
I bought an $8 float valve that you would use in an outdoor pond from Fish gallery in Renton. The purpose for the valve (as intended by the manufacturer) is to hook a garden hose to it... when the water level gets low the float lowers and alows water to flow.

I put the smallest adaptor to the float valve (so an airline could fit) and then ran that airline to a 5 gallon bucket that will sit atop my sump with the fresh water in it.

Inside the sump I used some light diffuser (the plastic grid stuff that people use as shelves in their aquarium) on end and secured the float valve to it and the diffuser to the plumbing in the sump.

When the water level goes down, the valve opens and allows a small, slow flow of fresh water into the sump... just like if I was home.

Works awesome... and will avoid any mess ups by those who do not hape a PHD in "my tank".

I will post photo's later.
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