Sump, overflowing main tank?

[Strawman]

So, I have the sump overflowing issue figured out, but my problem now lies in the return of pump powering back on after a power outage and overflowing my main tank. how is this rectified.

Also any suggests as what to do with the extra portion of my tank?

[BigJim]

In a properly designed system you don't need any flow control to prevent overflows when the power cuts out.

You should use an overflow box, not a straight siphon. Balancing the siphon flowrate to the pump flowrate is difficult and provides a lot of opportunity for flooding.

Your overflow should be capable of a higher flowrate than your return pump. You want the pump to be the choke in the system.

With the pumps turned off, fill the tank and the sump. If you don't add any water and your system is set up correctly, you shouldn't have any flooding when you turn the pumps on or off.

[Strawman]

My question is how do I stop the pump turning back on till the siphon starts, or automatically start the siphon once the pump starts

[BigJim]

An overflow box should maintain the siphon. The image below, courtesy of Melev's Reef, shows a HOB overflow box.

1. The water flows from the display tank into the leftmost chamber.
2. The siphon pulls the water up and over the tank wall into the center chamber.
3. The center chamber overflows into the rightmost chamber and down into the sump.

When the power is cut, water stops flowing into the first chamber and the water levels in the first chamber and second chamber will equalize , keeping the siphon tube full of water. The third chamber will drain completely.

When the power is restored, water flows into the first chamber again. The siphon is still intact, so gravity will cause water to flow through the siphon tube into the second chamber and overflow into the third chamber and down into the sump. No actions needed.




Here's all the sump information you'll ever need:
Melevsreef.com | Acrylic Sumps & Refugiums