How powerful should my sump pump be?

[rolikesfish]

Hey, well I am soon upgrading to a 40 gallon tank with a 15 gallon sump. Inside and outside of the display tank I will have overflow boxes, connected by a u-tube that will siphon the water down the plumbing. Once it is in my 15 gallon sump how powerful should my sump pump be? I was thinking a Maxi-Jet 1800 submersible utility pump, http://www.fosterandsmithaquatics.co...m?pcatid=18989
It is rated at 475 gph. The water will have to travel a good 4 ft up my plumbing so I am just wondering will this be powerful enough?
-Thanks!

[slumlord]

I'd think so, I run a little giant pump rated at around 800 GPH on a 55 and have it dialed waaay down.

[rolikesfish]

Oh, thanks. Do you know if you can dial down the Maxi-Jet 1800?

[discus510]

first off is the 475 gallon at 5ft?? r u plannin to T it off to any other equipment like a uv sterl a refug or any media reator if not and its rated at 475 gallon at 5ft its plenty for ur tank water from main tank goin to sump should be 4-6 times the water volume of tank so lets say 6 times it should be 240gph

[rolikesfish]

Thanks discus510 for the information about the water from the main tank going to the sump should be 4-6 times the water volume, I did not know that before.

[Gold Stripe]

This has been widely debated but in my opinion you ar looking for 4 to 5 times turnover for your display through your sump. Any faster and your skimmer, heater, etc will not function as efficiently becasue of reduced contact with the water. For a 40 that would be 200 to 250 gph at 4 ft of head.

Many people run much more than that because its easier to use your return for water movement in your display than set up power heads or a closed loop. But I think its better to keep lower flow through your sump and suppliment with the aformentioned power heads/closed loop.

[Jstdv8]

you have a HOB overflow. You need to match the pump to the overflow GPH.

[Chris27]

I usually go with about 10 times the tank volume - not accounting for head loss. So roughly speaking, a pump around 400 Gal / Hr at 0' should do the trick for you.

[Jstdv8]

how are you guys figuring all this 10x's stuff? He has to match the pump as closely as possible to his HOB overflow.
If he has a 600 GPH overflow it does no good to have a 1200gph pump.
You can only pump in as much as your overflow will alow you to siphon out via the overflow.

[Scuba_Steve]

He is talking about using a pump that flows way under his overfolws max rating. Your argument is moot. Now if he was trying to use a mag 18 or something, that would be another story. That pump will be fine.

[Scuba_Steve]

And btw you do not want to match your pump as closely as possible to your HOB overflow. You want to go quite a bit lower. Plan for the unexpected partial obstruction. Unless you like saltwater all over your floor...

[Chris27]

Originally Posted by Jstdv8

how are you guys figuring all this 10x's stuff? He has to match the pump as closely as possible to his HOB overflow.
If he has a 600 GPH overflow it does no good to have a 1200gph pump.
You can only pump in as much as your overflow will alow you to siphon out via the overflow.

Are you sure you're not thinking about matching an overflow to the tank volume? That would make a little more sense, putting a 600 Gal / Hr rated overflow on a 300 Gallon Tank would be insufficient, but on a 55 Gallon tank, it would be ideal.

The only restriction on the size of the pump vs. the rating of the overflow is the max flow, IE. The overflow is rated at 1000 Gal / Hr, so you can't have a pump that flows more then 1000 Gal / Hr at X' head.

[MCCOOL]

Originally Posted by Jstdv8

you have a HOB overflow. You need to match the pump to the overflow GPH.

This is incorrect.

I have a 20g sump and was debating between the maxi-jet 1800 and a Sicce syncra 1.5. I went with the Sicce, but the maxi-jet would have been a good choice also.

[MCCOOL]

Originally Posted by Jstdv8

You can only pump in as much as your overflow will alow you to siphon out via the overflow.

Correct, but the pump doesn't have to be as big as the overflow.

[discus510]

Originally Posted by Jstdv8

how are you guys figuring all this 10x's stuff? He has to match the pump as closely as possible to his HOB overflow.
If he has a 600 GPH overflow it does no good to have a 1200gph pump.
You can only pump in as much as your overflow will alow you to siphon out via the overflow.

no he can always pump more than wat his overflow will flow down to sump but the rest of water will be on his floor =) tats y he should use a ball valve to adjust water goin bak to tank

[iamwrasseman]

yes a ball valve will relieve many head aches and it will cost about $10 for the valve and two male barbed fittings which is all you need to do this . oops sorry and you will need two clamps too .$11 then ?

[dots]

Originally Posted by Gold Stripe

This has been widely debated but in my opinion you ar looking for 4 to 5 times turnover for your display through your sump. Any faster and your skimmer, heater, etc will not function as efficiently becasue of reduced contact with the water. For a 40 that would be 200 to 250 gph at 4 ft of head.

Many people run much more than that because its easier to use your return for water movement in your display than set up power heads or a closed loop. But I think its better to keep lower flow through your sump and suppliment with the aformentioned power heads/closed loop.

This is my philosophy as well. I will also mention that the DT tends to have a much higher velocity of water. This velocity has the ability to suspend both larger and in more volume of what we are trying to remove.

The lower flow of 4-6X has a significant lower velocity, therefore less capability to keep solids in suspension.....so at the very least when they are removed from the display, they have a greater chance in staying in the sump to be processed or vacuumed out later.

[dots]

Originally Posted by iamwrasseman

yes a ball valve will relieve many head aches and it will cost about $10 for the valve and two male barbed fittings which is all you need to do this . oops sorry and you will need two clamps too .$11 then ?

I believe ball valves can potentially add as many problems, if not more, than they "solve".

Most ball valves are required only after poor pump selection is made for the system and/or plumbing design.

A ball valves effect on a system curve is exponetial and as closed creates dramatic increases to static head in the system.

What this means, is what may have been a pump curve that was matched to the system curve in selection and is effecient, now shifts the duty points.....making the match most likely inefficient or worse moving dangerously close to the point of cavitation and ultimatly shorter service life of the pump. And I didn't even mention the reduction of flow to the system overall......

However, these things are often "overlooked" and or "disregarded". On a smaller system, it may be affordable or acceptable to use ball valves due to pump availability and or duty points (duty points: head and flow), so the observed effect to the reefer and the cost of a replacement is potentially justified. However, I find this dangerous as we tend to repeat those same mistakes on larger tanks where not paying attention to this can cause trouble with the cost/operation of the system, particularly when the pumps can be quite expensive to replace.

....ball valves or any valve should be used only if other means of splitting/reducing flow through plumbing design can't be achieved.