# GPH?????



## frogguy1 (Jun 9, 2004)

On my 120g FW piranha tank with large wet\dry filter I plan on running a 250 gph Overflow box that my local DIY guy is building. Does it matter if I run a mag 7 which is 700 GPH. With 4ft of head it will probably be nore around 600 GPH. What do you think?? I could always throttle it back, but I want optimal filtration


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## NTcaribe (Apr 8, 2004)

your over flow should bring in more water than your pump should so for a 1200GPH over flow you should be running a pump around 700GPH

you could use a ball vavle to decrease the flow,but most people will tell you that you shouldn't mess around with the flow

better to avoid the problem before hand

just my 2cents people correct me on my wrongs


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## wvarda (Aug 8, 2003)

Im running my overflow set up with 2 ball valves on the return and the intake. My intake is in a full syphon, with no air vents. This is the only way I could make it run silent. What are the problems that can arise from it? I just have to balance the 2 perfectly


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## frogguy1 (Jun 9, 2004)

Thanks guys, I called the guy building ,y overflow and told him to make it a 2 tuber rather than a single. This will make the flow of the return pump equal to the flow of the overflow.


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## Niche (Mar 9, 2004)

the flow of the overflow must be greater than the flow of the pump. they shouldn't be equal.


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## RhomZilla (Feb 12, 2003)

Moved to Tank and Equipment Questions


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## frogguy1 (Jun 9, 2004)

well once its throttled back It wont be equal.


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## frogguy1 (Jun 9, 2004)

Well after all the info from you guys and other people. I am going to go with an even bigger overflow with 3 tubes and a mag 9.


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## DonH (Jan 25, 2003)

Niche said:


> the flow of the overflow must be greater than the flow of the pump. they shouldn't be equal.


 I agree...

The filter pads in the overflow can clog over time and restrict the flow going into the sump. If you have the overflow rated the same as your pump, your sump can run dry over time. Also, I usually don't recommend restricting the flow of your pump to fine tune the flow because it can shorten the life of the pump and it's almost impossible to get it right in the long run. Purchase a pump that will work with the rating of your overflow and purchase a sump that will work for the size of your tank (must be able to take the excess water from the tank in case of a power outage or you turning the pump off).


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## frogguy1 (Jun 9, 2004)

The sump is huge, it used to be on a 180g. I will be for my 120g. I made the order to make my overflow bigger amd for a new pump. Finally got it right. now I just have to wait to set it up


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## NTcaribe (Apr 8, 2004)

frogguy1 said:


> The sump is huge, it used to be on a 180g. I will be for my 120g. I made the order to make my overflow bigger amd for a new pump. Finally got it right. now I just have to wait to set it up


 good luck with it

how much was your over flow and prefilter???,and where are you getting it?


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## frogguy1 (Jun 9, 2004)

I am having my local DIY guy build it fro me, his are better than any store bought overflow, plus only $75. And I am buying a mag 9.5 from the same guy i bought my wet\dry from. Mag 9.5 are normally $110+ and I am paying only $50(it was only used for 7 months, but last for severa years). I got great deals. I am a member of maast.org. A fish org in South Texas.


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