# ANOTHER sump question thread. gph related



## bremz8 (Apr 9, 2010)

so im building a sump, *** got everything just about figured out except for how much water ill be siphoning to my sump. im using a 1/2 inch pvc pipe inside of a 2inch overflow to pull water to my sump, and im wondering. how many gph will i be siphoning? what size pump should i get i cant seem to find a variable output pump so i want to make sure i get the right size water pump. thanks.


----------



## GTZ (Apr 21, 2010)

Found this here
3/4" = 330 GPH 
1" = 600 gph 
1 1/4" = 910 gph 
1 1/2" = 1,300 gph 
1 3/4" = 1,800 gph 
2" = 2,350 gph 
2 1/4" = 2,960 gph 
2 1/2" = 3,650 gph 
2 3/4 = 4,450 gph 
3" = 5,280 gph


----------



## Malawi_Junkie (Nov 26, 2009)

Here is a PVC flow rate chart which shows 1/2" PVC will flow about 420 GPH with just gravity.
http://flexpvc.com/WaterFlowBasedOnPipeSize.shtml

Take into consideration your head height when choosing a pump, this will affect your pumps output. If the pump you choose exceeds 420 gph at desired head height then you can use a ball valve to restrict the output or use a T connecting to divert excess flow back to the sump to prevent overflowing your tank.
What size tank?
What size sump?
Return line height (Head)?
Do you have any photo's?


----------



## bremz8 (Apr 9, 2010)

alright lets see
tank is 130 gallons
sump is 30 gallons
the tank is 24 inches tall on a 30 inch stand so 54 inches tall
no photos right now as i havnt begun the set up yet. im waiting on info to make sure i have everything i need.


----------



## Malawi_Junkie (Nov 26, 2009)

On a 130 gal. tank I would use a larger overflow like 1" or 1/2" x 2. 420gph is only turning over a little more than 3 times per hr. There is no perfect formula but most recommend 8 - 10 times volume per hr. If it were me I would shoot for at least 700 - 800gph.
Will you have additional filtration or just the sump? 
What are your plans for stocking?


----------



## bremz8 (Apr 9, 2010)

ok ill have to get larger piping then ok cool. id like to use the sump as my only filtration. but i have about 420 gallons worth of HOB and canister filters


----------



## paradigmsk8er (Apr 13, 2009)

I would definitely look for more then just 420 gph. On a 130 I would shoot for the 600-700 GPH ballpark, with close to 1000 being better but not necessarily essential. A good sump system doesn't need the 8-10 times turnover that most typical filters do, simply because of the incredible amount of biological capacity you can cram in one.

My two cents on the balance of overflow/return is...be careful. Sure you can gate back the return if you have too much pump..but it can * damage the pump, and 9 times out of 10 make the pump noisier depending on how much you gate back.

I started with a via aqua pump pushing 910 gph at 0 feet and switched to a quiet one pushing 780 gph at 0 feet and have been MUCH happier with the 780. I have the eshopps pf-1000 which is a dual 1" overflow. With the 910 gph it was much harder to get the balance right and much more sensitive....I cant count how many hours I wasted fine tuning the flow so it didn't overflow the main tank. The quiet one was SO much simpler. I have it barely gated, and just let it pump its heart out. The overflow will only flow as much as it is getting pumped back up. I noticed no difference in overflow noise or trickle either (though to be fair I do have some trickle noise inherent with my sump design that I am working on tuning out)

I know this seems counter intuitive and most things in the aquarium world are more/bigger is better..but for this I've found the opposite. I estimate I'm currently turning over 600gph + and have excellent bio filtration..in fact its staggering how low my counts consistently stay.


----------



## fox (Jun 11, 2009)

The part about bio filtration and sumps just does not make sense. It is mandatory for certain but should not be the primary function of any sump.

First and foremost design the sump around mechanical filtration. Then with whatever space is left toss in some bio media.

BB will attach where ever it can and unless you have a bare bottom tank with no scaping once your tank is cycled you would be better served paying more attention to mech filtering.


----------



## PauloSilva (Apr 17, 2006)

I'm planning out a 50g sump right now with a 125 display. My target it 10x turnover with a Mag18 pump. The sump will also be my only means of filtering. I would atleast try and get 1000gals/h. Why not?


----------



## Malawi_Junkie (Nov 26, 2009)

fox said:


> The part about bio filtration and sumps just does not make sense. It is mandatory for certain but should not be the primary function of any sump.
> 
> First and foremost design the sump around mechanical filtration. Then with whatever space is left toss in some bio media.
> 
> BB will attach where ever it can and unless you have a bare bottom tank with no scaping once your tank is cycled you would be better served paying more attention to mech filtering.


I for one disagree and believe bio filtration is far more important. Mechanical filtration is a must to remove all the little floaties but bio is what keeps your tank healthy supporting the nitrogen cylce. I posted a poll question so we can see what others think.


----------



## fox (Jun 11, 2009)

Bio filtration is overrated. This poll will most likely be along the same results as egg crates use in our tanks. Whatever rings yer bell.

I have practically removed all the bio media in my largest sumped tank trying to get out some misguided fry and have not replaced it in the last four months. No one died and my water is healthy. The BB just established somewhere else or increased its population elsewhere.

A healthy tank can get along just fine with the BB striving in the tank alone. Be Sure of it.

Now I posted certain conditions and this statement does not apply. I also stated bio filtration is mandatory. What I did not say was it was not needed.

Some thing are "understood" or "given", a sump will by nature add to the water volume and allow for hidden equipment. These are important aspects to a sump. If you have the space to toss bio balls and/ or scrubbies by all means do so. What I am suggesting is you just do not need as much as you might think.

Any sump designed lacking in mech filtration is basically a nitrAte factory.


----------



## Malawi_Junkie (Nov 26, 2009)

I just want to learn more about others experiences and maybe clear up some misconceptions that might be out there. My experiences with sumps are fairly limited as I have only been using them for about a year now. Most everything I have learned has been from this forum as well as trial and error. The best thing about this forum is the vast knowledge and experience of it's users and if I'm wrong about something I would like to know. We have different opinions on sumps so the poll question was to help clarify the issue.


----------

