Overflow? I'm an Idiot

[excuzzzeme]

On tanks 100 gallons or larger a wet/dry system is typically used as you can install a return pump with higher flow rates than a typical HOB can achieve. This is not to say you can't use one on smaller tanks as many people do so. A typical wet/dry (trickle filter) usually is a part of a sump system. The sump is simply extra water storage. When in a SW environment it is usually 1/3 of main tank size.

 

[Nolapete]

When used with just chemical and mechanical media, it's not a wet-dry any longer. It's just a huge version of a HOB.

 

[TEL]

Overflows are used on Wet/dry / Trickly filters. These are not for every one there are some good canisters out there but a properly setup and maintained trickly filter has a lot of advantages as stated above a place for heaters and other stuff that would normly clutter up the tank and you can use a greater veriety of media and gives you a greater volume of water which is always a good thing and if you decide to look at this type of filter overflows are not the only way to go you can also have your tank drilled and a bulkhead fitted which is what I did becaues an overflow if not setup properly will not always restart automaticly if turned off or the power goes out were as a bulkhead will.