My worries were more in case the main pipe would get clogged, lets say if a fish manage to get inside. I guess this is very unlikely anyway. In that case that the main pipe would be clogged inside, no emergency elbow would help. This is why the design with 2 overflow is a bit safer I tought.

That's why I went with the slotted pipe. No fish could get through that. And even your emergency opening can be covered with a slotted cap or something so that a fish can't jump in.

But your design there would work, too, with the 2 pipes. I just think it is a little overkill.

If the main pipe clogged, even a drilled tank overflow wouldn't prevent a flood. They're subject to the same rules in a scenario like that. Just hope it never happens when you're away for any length of time. Kind of why I'm a bit ok with my current sumpless set up. Although this thread has got me thinking I might get a sump going. I've been waiting to do that with a new set up, but these ideas have me itching to give it a try.

I rigged my overflow to work with a fluval 205 while I had my sump on order. It was pretty glamorous


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Depends on how you set it up. I have an emergency overflow the same size as my main that will never get a chance to clog with anything until my mainline completely fails. Then my emergency overflow would also have to completely get blocked before any water would get to the floor. I also put a cone shaped strainer on the emergency overflow so a large snail or the like can't completely block the opening either. And just to be on the paranoid side I used an external overflow with the back pane slightly lower and my sump directly underneath it so if there was an overflow problem the water would overflow my external overflow box and drop down into my sump which should catch most of the water. I think something similar could definetely be done with DIY pipe overflow without taking up too much realestate.

How did you set up your emergency overflow? Is it a completely independant overflow? or is it connected with the main overflow?

Another thing that worry me is if the return pump fail and the skimmer and heater are in the sump, then the temperature in the tank will drop and it won't be skimmer either. This is why I am worried about putting the heater in the sump. Skimmer is ok since it is ok to run without skimmer for some time.

[quote=intarsiabox;669100]Depends on how you set it up. I have an emergency overflow the same size as my main that will never get a chance to clog with anything until my mainline completely fails. Then my emergency overflow would also have to completely get blocked before any water would get to the floor.quote]

Here are pictures of the ones I made for some of my seahorse tanks.
DIY Overflow Tubes

The second pipe is in the overflow box but it is completely separate from the main drain. I don't know if it makes a difference but I also made the emergency drain a straight down pipe directly to the return section of my sump with no bends to slow/quieten the water down. As far as heat goes, my display tank is mostly covered as I use LEDs so it would keep the heat for some time without the water passing through the tank. I also have a new controller on order that will apparently email or text me if there is a problem. I've never used one before so I can't comment on how well it works. So far I've never had a heater or return pump quit on me so I really hope there is never a problem. I'm also lucky that my family is close by so if I'm gone for more than a day I get someone to check the tank. My biggest fear is the tank overflowing, not so much for the fish but for myself. My wife would probably drown me in what's left of the water if I destroyed her basement!

In my previous tank I had 2 fish that seemed to just love going for a ride down the overflow pipe and into the sump. At least twice a week I had to net them out of the sump. I used and still use 1 1/2" drain lines with no valves on them so almost any fish I keep will pass through without getting stuck. The pipe is a little larger than needed and you can hear the water going down the pipe a little but the only noisy part is the sound of the air bubbles breaking at the surface of my sump. I found a neat little design that gets rid of most of the air in the pipe before the water discharges into the sump and now it is pretty darn quiet.

The only problem I had with is a lot of noise but it was also in my bed room and not in a cabinet so I'm guessing there not as noisy as I thought :p