overflow, so many decisions....

[Delphinus]

I think some of the considerations will depend on what you want.

In some situations, you have a tank and stand, in a standalone situation. In this scenario you may prefer to have the bottom drilled so to minimize the plumbing outside of the stand.

However this at the cost of real estate in the tank.

A hang on the back overflow eliminates any space being used up in the tank, however with only one edge for the waterflow, can perhaps be prone to clogging more easily than say an internal overflow with three edges. However I don't think that's the hugest of concerns.

If you want to be really technical, then you should consider something along the lines of a "coast to coast" overflow. Feed your skimmer with raw overflowed water, the maximized overflow edge means maximized protein extraction (since proteins will float as a "surface skum").

To be honest though I wouldn't really sweat it too much. Make sure your overflow is sized for the flow you want it to handle, and have some fun. I've tried many different overflow styles and to be honest they're all the same in the end.. if they get the job done that's the most important.

However if I was to build a new tank from scratch at this point, I would be going coast-to-coast on the overflow. I let myself get talked into an "old school" corner overflow for my 280g by the builder... I do regret this a little bit, but I'm not changing it now, I'm not hauling that tank out my basement for that!! In the end it was little cheaper so I guess it wasn't a huge loss.

[mark]

Though unable because the way I display my tank, seems the coast to coast the best or even partial such as untamed http://216.187.96.54/vbulletin/showt...&highlight=400

Another interesting concept was what Dale has in this thread: http://216.187.96.54/vbulletin/showt...light=overflow

RC has a calculator for a smooth weir, and if you're interested send me a PM as I've got similiar for a slotted weir (I got fr RDO)

[Dave C]

One thing to consider with an external overflow is the space available behind the tank. My tank is about 2" from the wall, and that was where I wanted it. That ruled out an external overflow. A corner overflow is easier to hide IMO because it's typical to have a tall rock structure on one side whereas a tall structure in the middle isn't as attractive. I consider a coast to coast overflow but then I've got the entire back side of the tank using up the available width. I'm sure it skims better but I wouldn't want a shelf running the length of my tank. If I could go external that would be a good thing, but not internal. Again, these are all just opinions.