Is a DC pump really needed for a return??

[m.kristoff]

I just picked up a Ecotech L2 DC pump to run my return. It will push to the main tank about 6' away with a few 90's. I will also have a manifold to run a fuge, UV and future equipment.

the L2 is rated for 3K.

Everything will have a valve on it so I am wondering, what am I getting for the higher price of a DC pump? it will be ran full blast anyway. I have ran HY pumps in the past and never had any issues. Just trying to justify the cost

thanks

 

[Garf]

I just picked up a Ecotech L2 DC pump to run my return. It will push to the main tank about 6' away with a few 90's. I will also have a manifold to run a fuge, UV and future equipment.

the L2 is rated for 3K.

Everything will have a valve on it so I am wondering, what am I getting for the higher price of a DC pump? it will be ran full blast anyway. I have ran HY pumps in the past and never had any issues. Just trying to justify the cost

thanks

For me the DC just makes it easier to balance the syphon from the display. It’s just like having a gate valve on the pump instead of the drain.

 

[PeterC99]

Love my Ecotech M2 DC pump. Able to perfectly dial in the return pump for the flow in the sump. Controlled through the Mobius App and use considerably less energy than AC.

 

[Quietman]

Advantages of DC - controllability, quietness, less heat (if internal)
Advantages of AC - reliability, lower cost for given flow, heat (reduce heaters if internal).

So yeah...as far as simply moving water and you don't need the advantages of DC...AC pumps are fantastic. A good quality AC pump will last longer than most are in the hobby (DC pumps are getting better but will likely never hit the ruggedness of AC). You can easily control flow with a valve on output.

That said...my next pump will likely be DC. I don't mind buying one every 5-6 years and I like the quietness of tank in my living room. If my sump was in the basement then...hello Iwaki or Reeflo.

Edit: Forgot to add...backup power/flow is much easier to manage with DC pump if keeping filter flow is important in your backup plans.

 

[Jubei2006]

It is more quiet and energy efficient than an AC pump. I use a reeflo Hammerhead on mine. It's rated a 6000 gph, and has to push water up 18 to 20 feet. The only DC pump that might match that on the hobby side is the abyss brand. Which is waayyy more expensive than reeflo.

 

[m.kristoff]

AC pump will last longer than most are in the hobby

That is such a true statement!

Noise is not an issue for me. the sump and tank will be in the basement

 

[m.kristoff]

It is more quiet and energy efficient than an AC pump. I use a reeflo Hammerhead on mine. It's rated a 6000 gph, and has to push water up 18 to 20 feet. The only DC pump that might match that on the hobby side is the abyss brand. Which is waayyy more expensive than reeflo.

That's my question, is it really more energy efficient? If i am running this wide open and controlling the flow with valves, the Draw is 130watts

 

[Quietman]

DC motors are more efficient due to how they create a magnetic field. Somewhere are 30% more efficient I believe. But they are more expensive so the cost adding in electrical power over the 5-10-20 year life of a reef tank might be significant or break even depending on size of system and how long it runs.

But if you're talking total system efficiency and it's internal use then you'd have to calculate how much heat the pump adds and removing the needs for bigger heaters which is going to up the AC value. Pennies a day for electrical power isn't something I concern myself with, but it is interesting.

 

[Dunc]

I just picked up a Ecotech L2 DC pump to run my return. It will push to the main tank about 6' away with a few 90's. I will also have a manifold to run a fuge, UV and future equipment.

the L2 is rated for 3K.

Everything will have a valve on it so I am wondering, what am I getting for the higher price of a DC pump? it will be ran full blast anyway. I have ran HY pumps in the past and never had any issues. Just trying to justify the cost

thanks

I have a Sicce Syncra 7.0 DC pump on my mixing station. I run it full blast and it overheats. Shuts its self off. If I had to do it over I would get an AC pump for this application. If you can handle a louder pump go for the AC. Like you said, you can control flow by the valves.

 

[trainbob]

If you have a DC pump for your return you don’t need a valve to control flow. So one advantage for a DC pump is one less failure point both for leakage plus a valve can fail.

 

[Spieg]

If you're controlling flow with a valve `then I wouldn't use DC. Most DC pumps don't like to run against a valve. Kind of defeats the purpose.

 

[Jubei2006]

That's my question, is it really more energy efficient? If i am running this wide open and controlling the flow with valves, the Draw is 130watts

That's my question, is it really more energy efficient? If i am running this wide open and controlling the flow with valves, the Draw is 130watts

Look at the hammerhead draw, its between 270 and 370 watts, so double the draw.

 

[m.kristoff]

If you're controlling flow with a valve `then I wouldn't use DC. Most DC pumps don't like to run against a valve. Kind of defeats the purpose.

I am running a manifold so I will need the valves to balance

 

[Spieg]

I am running a manifold so I will need the valves to balance

That's probably okay as long as there is one line that is not slowed down.

 

[Quietman]

If you're controlling flow with a valve `then I wouldn't use DC. Most DC pumps don't like to run against a valve. Kind of defeats the purpose.

There is nothing inherent in a DC pump which prevents adding an output flow control valve. It's simply the pump running against a higher head.

I can see a good use case for that in a manifold as well since you need different flow rates for different equipment.

 

[Spieg]

There is nothing inherent in a DC pump which prevents adding an output flow control valve. It's simply the pump running against a higher head.

I can see a good use case for that in a manifold as well since you need different flow rates for different equipment.

A DC pump running against higher than normal pressure will build more heat and require more power... why spend the money when AC would work as well? Don't get me wrong. I run a DC return and am very happy with it but don't run it through a manifold when a properly sized AC pump would be a better solution.

 

[Midrats]

There's no electronics or power supply to fail on an AC pump. I always go AC for returns.

 

[Quietman]

A DC pump running against higher than normal pressure will build more heat and require more power... why spend the money when AC would work as well?

I was only commenting on the "don't like to run against a valve" which implied causing damage to pump/motor. If you're talking cost effectiveness I suppose that's up to the user and how it's implemented as much as pump/motor design under ideal conditions.

edit: I suppose there could be a higher work load will reduce life time of equipment vs running under low work load condition but that's true of everything.

 

[Jubei2006]

DC pumps struggle against head pressure. If there's anything more than about 4 to 5 feet, I wouldnt use a manifold and create more back pressure. In the situation honestly Id go two DC pumps, one for return, on for manifold, or a larger AC pump that doesnt mind head pressure as much

 

[Chrisv.]

The high end AC pumps are also EXTREMELY quiet.

For my money, an eheim 1262 is the perfect pump for a mid size reef return if the sump is under the tank and not in a basement or something. 900gph, capable of dealing with head pressure (though it does decrease flow).

The eheim 1262 and Tunze Silence series ac pumps are quiet enough to run in a mosuleum.

They are built like tanks too.