Internal vs External Overflow

[RitchieKy]

Hello,

For my next tank I'm looking at either the Innovative Marine 75 Int or 75 EXT.

All of my salt tanks in the past have had the traditional internal overflowers with the bottom drilled.

I was considering the external overflow so that I wouldn't lose the space inside the tank. On the IM 75 Int, the overflow eats up 5" in the middle and 2" on the back sides.

My question for those of you that have used tanks like this with the external overflows, how annoying was it to not be able to put the tank closer to the wall? On the IM 75 Ext, the overflow box is 3.5" front to back. I may position the tank with one side against a wall and the other side against my desk, or I may position the tank against a wall where one side would be open. I was curious as to how aesthetically unpleasing this may be?

Thank you.

 

[Rp8]

I have and prefer the external overflow. Being off the wall allows for better access to pipes and plumbing. Easier to punch pipes clean to knock out buildup and filter feeders drain or return.

 

[Rp8]

On the internal overflow I have always had a ton of pineapple sponges and other filter feeders that kinda takeaway from the tank

 

[The_Paradox]

Most people leave a few inches behind tank anyways, especially if they are running something like Ecotech pumps, so I don’t see that as an issue. Only time I used an external over flow was on a 40gallon decades ago and it worked fine but did leak on me once. Externals do tend to put more stress on the glass/seals. Since that time I have learned if it can leak then it’s going to leak. Personally I usually do something like center over flow with 3-4 holes inside 9x3 box. Whatever you choose. I’m sure will work fine it’s more about what you personally prefer.