DIY Auto top-up

[BFG]

That's a good idea! For my case, I customized a small but tall acrylic container that occupy a small corner of my cabinet. Even if the equipment fail for whatever reason, my water would not overflow my tank as it is only about 10-12 liters. I could have forgo a cheaper alternative but reading from other forums about the risk of float valve led me to my current choice of equipment. Yes it is pricey but there's no chance of further upgrade as this is where the technology ends. Been using it for about 4 years and it has work flawlessly. Set and forget.

[tawauboy]

Thomas, there is a high risk factor to using this setup. Float valve are not generally fool proof and if a snail happen to be where the float valve suppose to 'close', there will be an uninterrupted supply of water being fed into the tank. Knowing that the tap is connected to the water tank, the tank will soon overflow with water and flooding the house it is kept in. The missus will not be happy when she reaches home. I remembered our former moderator Kelvin had this happened to him.

.......

i didn't think about the snail part. i guess you'll probably need some sort of screen to prevent snails getting in.

[RonWill]

Intending to make a DIY auto top-up system with a battery operated airpump, float switches...

Edward, I'm not sure how relevant this old thread might be to you but it does eliminate most of the flooding issues. Admittedly it isn't the most aesthetic approach but hey, I'm skittish with too many wires running around the tanks and the original purpose of the float valve was unattended water changes.

If your tank was already pre-drilled to accept bulkheads, and you have access to water mains and drains, daily but small water changes won't drastically affect the fishes.