SUmp Pump Help.

[Virtual-Liquid]

Hello all, I am new here and somewhat new to SW stuff.

Here is my problem, I have a 30g non drilled tank, and a 29g tank I plan on using as my sump, it already has the baffles in it and a custom plexi lid for 1 1/2 tubing to fit through. I have everything except a overflow box, I have been looking online with out much success in finding something I like. I have everything I need to start a sump including the return pump which is a mag drive model 7 ( 700gph), which I think might be too big.

The things I am confused on is, what is a good overflow box, and if I can easily build my own, what size tubing do I need to use to match the return pump flow.

Thank you in advance :)

[Phurst]

It's almost certainly easier to buy one than build one. Is there a reason you wouldn't have the tank drilled? Is it tempered glass? The reason I ask is, even the best overflow boxes are prone to failure. Many of them will not automatically restart their siphon after you turn off the return pump. If for some reason your power flickers long enough to break the siphon, when the pump kicks back on, you're looking at a flood. Also, bubbles are prone to getting stuck in the U tube of overflow boxes breaking the siphon. I've never used an overflow box, so i can't reccomend one particular brad, but those are some things to look out for/keep in mind.

A 1" drain is rated for 600 GPH in ideal conditions. After head loss and plumbing necessities, your MAG 7 should be under the 600 GPH threshold. There is a great head loss/plumbing loss calculator here:

Head Loss (http://reefcentral.com/index.php/head-loss-calculator)

that should tell you roughly how many GPH to expect out of your pump in your situation.

[saxman]

i agree with Phurst...if you can drill the tank, you'll be a lot happier. that being said, i ran a U-tube type O/F box for years, and never had any trouble with it (you need to take a peek at the U-tube and knock any bubbles out of it or remove it and clean it as a part of your regular tank maintenance). it never once broke siphon.

the CPR-style of O/F boxes do have a reputation for not starting back up after power outages, so they require an "aqualifter" pump (sold separately). once you install the pump, i'm told they're pretty reliable, but if i had to pick, i'd go with a U-tube type. you can even add a second U-tube for redundancy if you like.

HTH

[Virtual-Liquid]

Thank you for your opinion's, after I could not wait, I decided to build a mock up situation, same plumbing measurments and everything, just used a 10g display and the 29g sump, and my results were not pleasing, I used 1 1/4" pvc with ball valve for the siphon, no over flow box just a straight pipe in the water ( this would have been temporary if it had worked correctly, and a box would have been built) and for the return I used the standard 3/4" pvc for the mag pump. After a few hours of testing, the siphon failed because it would drain faster than the return pump or the pump was too much for the siphon.

Conclusion is, if this was on my real tank, after a few tweaks and modification, it would ultimately end up on my floor leaking to my basement, so no im looking into some local area stores to get my tank drilled if possible :)

Thank you very much for your help and opinions, as it was more or less the deciding factor in it all..

[rayme07]

Hi Eric Welcome to TR.

[CarmieJo]

Hi Eric :welcome: to TR.