1. There are well over 130 mechanical water levelers available today, and none of them can be guaranteed not to stick in the closed position.

The most common of these are the cheap plastic ball valve usually found in toilet tanks, which are notorious for warping and jamming.

There is a more modern version that can have as many as 15 various moving parts that can malfunction, resulting in a continuous flow.

Even the more costly brass valves cannot stand up to acidic or corrosive water and over time will corrode and stick.

2. As a rule, most koi farms, koi breeders and koi pond owners boasting of expensive, prized koi fish will not trust their treasures to mechanical auto fills.

When a mechanical water leveling float sticks, jams, warps, rusts, corrodes, it malfunctions, in the open position, resulting in continuous water flow.

In most cases, with the exception of filtered or well water, a stuck float can result in the chlorine poisoning of the pond's inhabitants.

3. A mechanical float should be installed for the convenience of the pond owner, not the pond builder. In their quest for higher profits, pond builders are using cheap, easy to install, pond liners, which are more susceptible to leaks than concrete.

According to statistics from the pond liner industry, "1 out of 3 rubber liner ponds & waterfalls are leaking within 9 months of completion.

Dishonest and lazy Liner pond builders will install the cheap Aquascape water leveler to hide the leak issues from their customers, only to be discovered later as a result of high water bills or serious water damage.

Conclusion: If you must have a leveler on your pond, I would suggest using an electronic float, not a mechanical one. There are only two manufacturers of electronic floats. The AquaFill and the Levelor controllers. The AquaFill is the only water leveler float that carries the "fail-safe" rating. The main issue with not using them is, you still need to add water to your pond and as a consequence, many people use a garden hose to fill their pond and forget or become distracted, forgetting to turn off the water, the result being the same as a stuck or jammed float.

Author's Bio: 

Douglas C. Hoover; CEO of Aquamedia Corp, Master Waterfall Builder, architect, engineer, author, designer & builder of over 1,900 waterfall and ponds(29 years). Author of "Waterfall and Pond Construction Manual." Learn more at http://www.aquafill.com.