help building a overflow

[ilostnemo]

im going to build a overflow from my display tank to my sump and i was wondering how i can build one that will resume working if power goes off than back on so that the return pump wont over flow the display tank. anyone have a design that works like that?

 

[corrado33]

I built one using this design. It worked well, but you need a vacuum line to keep the air out of it.

DIY Overflow Box

Many people suggest building overflows using "U tubes" as they don't need the special vacuum line. I don't have a link for one like that.

 

[ilostnemo]

would something like this work and not lose its prime Quietfo Hang-On Overflow Box - Clean, unused condition - eBay (item 150421055076 end time Mar-11-10 19:25:00 PST)

 

[ilostnemo]

or this one Eshopps Aquarium Siphon Overflow Box 125 Gal PF-800 N - eBay (item 110505061351 end time Mar-14-10 21:05:18 PDT)


and by vaccum line do you mean just airline hose attached or actually put onto a vaccum,

 

[corrado33]

I can't tell if the first one would lose it's siphon or not, but most correctly built overflows don't lose siphon (or else they'd be useless). The second one is built to not lose siphon. You should remember though, you should get an overflow box that is suited for your specific tank. Getting one that's rated for a much higher flow rate than you will be using won't work well, as the flow through the tubes won't be quick enough to stop bubbles from collecting in them, therefore stopping the flow.

And by vacuum line, I mean air hose line that's generally connected to the output of a powerhead (which in turn draws air out of the overflow tubes).

 

[jawbreaker1222]

Nice Cheap DIY Overflow - Page 7 - 3reef Forums

I built this for my tank and it has worked flawless for a fiew months. It will restart siphon after a power failure. I made mine out of 1 inch and it is handling around 300gph. Total cost was around 18 dollers. I tried inch and 1/2 but it diddnt work out.