External Overflows

[TheReefGeek]

This is in another post too, but if you are getting a new tank, get it drilled for an overflow, and preferably for a closed loop.

You don't need a trickle filter, or wet-dry, or canister. In the sump you can hold your heaters, add more water volume, put a refugium into it, and is a good place for an auto top off.

Personally I'd avoid the U-Tube style as they have no ability to clear bubbles which could get into the tube.

This is not true. You can drill a hole in the top of the u-tube and install a 1/4" airline to let air out. And a u-tube overflow can be very safe if implemented correctly.

1. If the siphone quits, what happens? Your return pump keeps going, and empties just the return section of your sump into your tank. Make your return section small enough that your display can take the extra water, and there is no way to flood.

2. But then your pump will burn out, if this is a big concern, install a float switch to kick the pump off if the water level gets too low.

3. Make sure the model you buys keeps both ends of the u-tube sumberged if the power goes out, this way siphon will not break, and flow will continue when power comes back on.

4. Block light from getting ot the overflow, this way nuisance algae will not grow as much and potentially clob things up.

5. Regular maintenance, if you have done the above, weekly should be more than enough.

Those reccomendations are for those with setup tanks who are running an external overflow already, or who want to add a sump without disturbing their tank. If you are starting a new tank, get it drilled like swiss cheese and you will be happy you did. If you are handy, you can order diamond hole saws from hongkong for less than $5 a piece shipped to your door, and drill yourself.