Overflow for Rimless Tank

[dreamcatcherr9]

Internal vs External overflow.

Besides aesthetics and distance to wall:

For a rimless tanks, what’s better. Would one or another allow for more water (higher level) in display tank?

Which would you pick? Amount of drilled holes / bulkheads? Style or brand of overflow? Location?

Let’s say a 240g ish tank (6ft long).

Just curious what someone who knows what there doing would do...

 

[dreamcatcherr9]

Any thought , suggestions or opinions?

 

[Water Dog]

Go external with a low profile internal skim box. Choose a reputable company like Modular Marine or Exotic Marine Systems. IMO it’s better than an internal set up that takes up too much room in the DT. Before setting up my 57 gallon rimless, I had my heart set on a Red Sea Reefer 250. The amount of space that the internal center overflow tower turned me off. I much prefer the aesthetics of the slim ghost style overflow from Modular Marine that I ended up with. Left me with much more room for aqua scaping and unimpeded flow for my MP40s.

For a 6’ long tank, the external style ghost overflows give you the option of longer 36” plus internal skim boxes for much better surface skimming. Now compare that to a Reefer 750 and the amount of surface skimmimg is miniscule relative to the length of the tank due to the very short span of the weir teeth on the internal overflow tower.