Is there a formula to calculate sump size?

[Fuzz]

Hi All,

Anyone knows how to calculate what sump size to use for a 4ft x 2ft x 2.5ft tank ?

Will a 2.5 ft x 1.5ft x 1.5 ft sump be sufficient?

I'm be using MD50... or do I lower the pump to a Eheim 1260??

Need Advise

[cityofangels]

I don't think there's any specific formula for sump size. Sump wise, people try to go as big as they can go.. In case, they would want to add more stuff in their sump, e.g. refugium, CR or FR, in-sump skimmer etc.

[Fuzz]

true.... but if I only have a 2.5ft sump, will it work with a 4ft tank? Does that means that I have to reduce the return pump flow rate?

[madmac]

In doing the sump, Melv in RC uses a 3 to 5 times main tank ratio. In other words, it doesn't matter how you design, the physical dimensions of the tank, be it long or broad, the return (pump) should be 3 to 5 times your tank.

Sump design can be very challenging and rewarding if done to your needs. It requires that you know your skimmer, in sump/or out sump, pump location and placement hight, etc.

Try to look out for his sump design page, it fantastic, with tens of sump desings pics, considerations you must put, etc.... sorry I lost the link to it

[yus75]

my sump covers almost the whole base of my cabinet...wich mean almost the same size of main tank lenght n wide....

[cityofangels]

madmac was referring to this site: Melev's Reef Side

You can try these other sites for ideas on sump designs.

Skimmer & Sump Designs

Lifereef Filter Systems ---> Scroll down, towards 3-quarter of the page and click on "Custom Sumps & Systems".

Hope the links are useful!

[madmac]

madmac was referring to this site: Melev's Reef Side

You can try these other sites for ideas on sump designs.

Skimmer & Sump Designs

Lifereef Filter Systems ---> Scroll down, towards 3-quarter of the page and click on "Custom Sumps & Systems".

Hope the links are useful!

yeah thx CoA, and I guess this would be it : http://www.melevsreef.com/allmysumps.html , now for me to bookmark it.

[atos]

If you rely on the skimer as a main fisical filtration, than you do not need any rush trough the sump of the water. It means that your return pump should not be any stronger than the skimer pump. What is the reason for water rushing trough a sump several times faster than the skimer pump could handel ? In tank circulation, this you should consider maybe 20-30 times the volume of the tank.

[madmac]

give us some numbers, its easier that way... keep in-tank flow away for the time being.

[Fuzz]

Thanks for all the in-sight...

my main concern is that there is a power trip and water backflow into sump and sump cannot handle the back-flow of water...

I'm using MD-50 with RM 30inch beckett (out-sump)...

any advise for my 500L tank... and 140L sump... what is a safe flow-rate pump?

So if it 4x - 5x ... then my pump shd max at 2500 L/hr pump?

[atos]

Did you run your setup? Have problems? How the sump could't handle the overflow?

[Rocks]

Thanks for all the in-sight...

my main concern is that there is a power trip and water backflow into sump and sump cannot handle the back-flow of water...

I'm using MD-50 with RM 30inch beckett (out-sump)...

any advise for my 500L tank... and 140L sump... what is a safe flow-rate pump?

So if it 4x - 5x ... then my pump shd max at 2500 L/hr pump?

if you are concern about back flow, try using check valve to prevent back flow when power trip. I have mine installed just after the return pump, it once prevented a over flow when my power tripped while I am not at home.

CHEERS!

[madmac]

Thanks for all the in-sight...

my main concern is that there is a power trip and water backflow into sump and sump cannot handle the back-flow of water...

I'm using MD-50 with RM 30inch beckett (out-sump)...

any advise for my 500L tank... and 140L sump... what is a safe flow-rate pump?

So if it 4x - 5x ... then my pump shd max at 2500 L/hr pump?

There is a elegent method to prevent backflow... drill a small hole at the outlet pipe. In the event of a power outage, as the water goes down in the main tank, air wil enter the hole, then the back syphon will stop. I think they call it a "syphon break"... or something like that.

yeah, 2500l/h should be right, make for some loss here and there and you can even go for 3000l/h. At that rate, your water is passing thru you sump at 20 times.

Now if you are going for a 3000 l/h pump, then choose a skimmer pump that drives, slightly lower, about 2500 l/h... that way 5/6 all your flow goes thru the skimmer. Now that you know this go and buy the skimmer thats rated for this and you jus right sized it all.

[mUAr_cHEe]

how about:

( biggest size possible for your sump / smallest size possible for your sump ) X (Tank size / 3.5) X $$$ available for you to blow on ??

[Fuzz]

Did you run your setup? Have problems? How the sump could't handle the overflow?

I haven't run the setup... I'm buying a 4ft tank, but it's sump is the same size as my 2.5ft tank sump... so it is a concern too...

[Fuzz]

if you are concern about back flow, try using check valve to prevent back flow when power trip. I have mine installed just after the return pump, it once prevented a over flow when my power tripped while I am not at home.

CHEERS!

[Fuzz]

There is a elegent method to prevent backflow... drill a small hole at the outlet pipe. In the event of a power outage, as the water goes down in the main tank, air wil enter the hole, then the back syphon will stop. I think they call it a "syphon break"... or something like that.

yeah, 2500l/h should be right, make for some loss here and there and you can even go for 3000l/h. At that rate, your water is passing thru you sump at 20 times.

Now if you are going for a 3000 l/h pump, then choose a skimmer pump that drives, slightly lower, about 2500 l/h... that way 5/6 all your flow goes thru the skimmer. Now that you know this go and buy the skimmer thats rated for this and you jus right sized it all.

[Fuzz]

Ok... I've worked out that my 2.5x1.5x1.5 ft sump can hold a max of 33L more before it overflows with water from my current tank...

So if we calculate that 33L for my 120Lx60B tank... I will get a 4.5cm depth... max

Question now as long as I place all my return pipes above my 4.5cm mark, it should be ok, correct?

Anyone got insight on this?

[atos]

Fuzz, this gif image could make your life easier . Look it carefuly, notice the small ciricle on the return pipe, that is the hole small that have to be drilled, it will brake the sifon once the power failure, it will suck air and stop the back flow

[May&Bruce]

my rule of thumb is to use the biggest sump that you can fit/afford. Apart from giving you lots of room for putting equipment, the greater the sump volume means the greater your total volume of water and the benefit of this is that the more stable your water parameters will be.