Overflow size & Mag pumps

[Michelle L]

I have searched through the forums and can't really find what I am looking for. Sorry!!

I am setting up a 125 gallon reef system, and my tank isn't drilled. I'm not willing to risk drilling it myself and nobody in my area will do the job, so I am going to have to use overflows on the back of my tank. I have a 55 gallon sump/fuge underneath the tank.

What size overflows will I need to get adequate turnover in my tank? What is the ideal setup for that? (One overflow, two overflows, three, etc.?)

I had sort of planned on using two overflows (one on each end of the tank) and run two Mag drive pumps to return water to the DT. What size pumps will I need to get adequate turnover?

Also, what is the ideal turnover rate for a 125 gallon reef? I had read that 25x is ideal, so that means I would need to circulate about 3200 GPH?

Thanks!!

Michelle

 

[purza_00]

Two overflows are definately the way to go. You have one skimming the surface crud at each end of the tank. Additionally, if one should become blocked the other may prevent an overflow (spill). Most of the hang on overfows I've seen run at a peak of approximately 600 gph. I would think that you could have some made to handle much more.
Someone with more experience should be chiming in soon.

 

[Michelle L]

Actually I have found that CPR makes a 10 inch overflow that handles up to 1600 GPH (at least, that's what they say) and various sizes up to that. I was thinking along those lines. I was just wondering what size pumps mated with what size overflows....I'm just scared to death to plumb this thing wrong and flood my house!!! :eek1:

Thanks for the input!!

 

[purza_00]

Using the head calculator on the home page and the head loss chart for various pumps you can find one. Sump design and plumbing will also be important as you have stated. Best wishes on your system and help should come along soon.

 

[bertoni]

That total amount of flow is fine, but I wouldn't run that much through the sump. Maybe more like 500 gph or so. The rest of the flow could be delivered by a closed loop or powerheads.

 

[nm354]

My 75 has a HOB overflow w/ two U-tubes. I am running a mag 12 wide open for the return without a problem.

 

[sjm817]

You dont want the return pump delivering too much display to sump circulation. That is not what it is for. A 125G should have ~ 375 - 625 GPH provided by the return pump. The majority of display circulation should be provided by powerheads or closed loops.

I would also advise against the CPR overflow. They do not maintain siphon on their own and require a vacuum pump to do so, and then it is still unreliable. A Lifereef would be a much better far more reliable option.

 

[Michelle L]

Okay, thanks everyone, that answers a lot of my questions!....sjm817, I found the Lifereef website and I have to thank you. I hadn't read about them before and they sound great...I have been worried about losing siphon and flooding my floor with CPR's or something similar. Should I go with a single, with a flow rate of 700 GPH, or the double, with a flow rate of 1400 GPH? From what I am reading here, I should stick with the smaller model?

 

[sjm817]

The single LR is fine as long as you keep the return pump size reasonable. I use one with an Eheim 1260 return pump.

 

[bertoni]

I would stick with the smaller model, too.