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Overflow question?


Oct 21, 2013
Hello all,

I am fairly new to octopus keeping but not new to saltwater aquaria.

I'm going to setup a 50 Gal Seaclear Arylic Caribbean Reef Octopus tank with a 20 Gal sump and a 10 Gal fuge with a eheim 1260 pump that will provide all the flow in the display as well as a few reactors no powerheads. And I was wondering if the Reef Savvy External Ghost Overflow will do and if not what would be the ideal overflow?



Sepia elegans
Staff member
Jan 6, 2005
Dancing between Vancouver and Auckland
Hey there dylanmegyptian. Welcome to Tonmo! No need to bump the thread quite yet, haha, we jast had our bi-annual conference over the weekend, so many of our members may still be traveling home, and simply have not had time to read this thread yet. I, unfortunately, have had no experience with running aquaria, but am sure that one of our other members will post a resonse soon.

Once again, welcome to TONMO, and I hope you questions is answered shortly! :smile:


Colossal Squid
Nov 19, 2002
Dunedin, New Zealand
I'm not familiar withis particular model, but so long as there are no gaps I don't see why not, be aware tho octopus can get out of very small gaps.......size of their beak. They can also be fairly destructive, We've had them rearrange tanks on a regular basis!


Staff member
Sep 4, 2006
Gainesville, GA
I like the idea for that overflow and I see no difference in placing one like this in a tank vs a built-in EXCEPT the ease of removing the grid (grid opening size is always a consideration). I would highly recommend adding a latch to secure the grid section. This is the one I use:


on my tank lids and I know it is all acrylic. Be sure there is no metal pin in the hinge as even aluminum will corrode in saltwater. Unfortunately, I can't recommend a proper pin for securing the latch as the thin rods they carry are either slightly small or slightly too large. I use piece of bamboo skewer or the too small rod and bend it with a heat gun (which makes them brittle).

The size of the grid openings can be problematic, depending upon the size of the animal and WILL be an issue if you have hatchlings. Any opening larger than the eye (as Jean mentioned, the beak is the actual restriction but the eye is something you can see and is about the same size) is a problem, especially if it leads to a nice dark hole. So far, my best answer for minimizing interest is to place a very course plastic sponge (like those used for air cleaners) directly behind the grid. It will require cleaning but should allow enough water flow not to backup the tank.

If you are installing it yourself (vs pre-installed) consider placing the overflow holes so that the tank has roughly 2" of dry space at the top. This air gap goes a long way in helping to reduce escapes.

If you are building out your tank yourself, please consider journaling the progress and decisions in our Tank Talk thread. You will find numerous ideas for the lid there if you need some ideas.

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