Mr. Saltwater Tank

Write-Up Wednesday: DC Return Pumps


Return pumps come in two flavors, dictated by the electricity that runs them. AC return pumps run on alternating or “AC” power while DC return pumps run on direct current or “DC” power.

AC pumps have been powering our tanks for a long time with a good track record so why fix something that isn’t broken? There are a couple of reasons why these DC pumps are marketed as “better” than their AC counter parts:

Control

A DC return pump gives you the option of variable speed control which means you can now control how much water flows out of the pump. Contract this feature with an AC powered skimmer pump that is either on 100% or off.

This control comes in handy in a return pump as if the flow rate is too much, simply turn the pump down. Need more flow back into your tank? Crank the pump up! Remember that you’ll still need to know approximately what flow rate you need as if you need flow that is beyond the capabilities of the pump given your head pressure, you’re out of luck.

Flow control is achieved through an included controller where flow can be dialed up or down. These controllers often include a built-in feed timer that will shut off the pump for a number of minutes while you feed your fish.

Finally for controllability, DC pumps have a “soft start” feature meaning the pump starts at a low rpm and ramps up to full speed, potentially reducing broken impellers.

Efficiency

DC pumps are more efficient than AC pumps. In other words, it takes less electricity to get more performance out of the pump. That means a smaller electric bill. (I highly doubt that you’ll see a drop in your home power bill if you switch to a DC return pump, but hey, it makes for a great selling point!).

While these DC return pumps look promising, I’ve avoided them for one big reason: quality.

I’ve talked to several saltwater equipment retailers that tell me that they have stacks of dead DC return pumps. I’ve also talked to several other professional saltwater tank installers who have had multiple failures of these pumps.

For the pumps that are still operating, I’ve run across countless stories of the controller for the pump being hot to touch including one instance where the client called the service company to complain about the heat of the box!

I like the concept of a DC-driven return pump and I’m still avoiding them until I see a DC return pump of real quality.

Browse the Store! Questions?

Comments for this article (21)

  • Allen Jackson says:

    So I like what u have to say about DC great points! I would like to add another benefit you could always use a few deep cycle marine use batteries to get you through a power outage to keep the flow going. Use an ac when power is on use dc when power is off!

    Happy Reefing

  • Steven says:

    What return pump do you recomend for a 90 gal. Also I think that many AC pump are poor quality as well.

  • Mohamed Alnuaimi says:

    You will never get electric shock with DC if in case wire was cut:), it is more safe

  • Steve says:

    I have a Jebao DC 6000 on my 55 gallon and have not had any problems with it.
    I put it on when my QuiteOne 3000 died.
    I originally bought it for my 90 build that I’m in the process of, but I think it might not be enough flow for the 90 so I got a DC 12000 for it.

    Another plus of the DC pump is that the all seem to have the same 3 prong waterproof connection that the Jebao WP pumps use, so you can make a cable or get the Jebao from Reef Angle and the pump can be controlled by your Reef Angel or Apex controller.

  • Vic Brincat says:

    So the major advantage of DC return pumps is control.
    Anything wrong with a gate valve inline with an AC pump?

  • Jeffrey says:

    As far as getting shocked goes DC is just as dangerous as AC. Its just we do not come into contact with high voltage DC very often. 24v will not shock you be it AC or DC. But 120v of either certainly will. I only point this out to dispel the myth that DC is safer. Both can kill.

  • Johan Wilson says:

    Another big benefit to the dc pumps being more efficient is less heat transfer. With ac pumps I have to run a chiller on my tank but with the dc pumps I do not. I agree with the quality issues. Most pumps on the market are some version of the jebao. The waveline gen II seem to be of higher quality and run at a higher head pressure than the gen I but still tend to drop in power over time. If you go the DC route I would buy a bigger pump than you think you need since you can dial it back. In these pumps head pressure is the more important spec than flow. The difference in flow between a 10k and 12k pump can be more than double in your tank. On the quality front there is always red dragon but not many of us have that much $!

  • Mohamed Alnuaimi says:

    Jeffrey: you are right & I understand your point but most of the DC running in low voltage & in some point it is still safer than AC, I am not saying complet safe.

  • Damion says:

    I am currently running a dc12000 on my 90 and run it at 50% to achieve my flow rate. At 100% it can run my sump almost dry! Longevity has yet to be seen.
    I really like running it from my controller.
    It has a slightly louder wine than my last AC pump, that only I can notice. I’ve also found it puts less heat into the tank. And I like the price! I can get at least 2 of these for the price of a comparable AC pump. I’ll be putting in a flow switch as an alarm feature just to be safe.

  • Dan says:

    I agree with the gate valve comment from Vic. I does not hurt the pump… I like simple….

    On a side note has anyone had a chance to use the Maxspect Gyre yet? I replaced 7 powerheads with 1 Gyre in in my 180… 35 watts and i am only running it on 50% power and pulsing. i am going to use them in my frag tanks as well.. 1 cord in the water and the flow is insane. since it is on the side of the tank you don’t really even notice it. I love this thing, the real test will be durability. The demo video from MACNA with the ping pong balls does not do the pump justice. Every corner of my tank is moving, rock work does not seem to matter.

    Mark I would be curious of your take on it if you do a review.

  • steve dodd says:

    if you want to control the speed of a A C pump , just conect it to a dimmer switch , then you can run it at what speed you want

  • Damion says:

    Not all AC pumps will like a dimmer…
    Proceed with caution…

  • Dave.M says:

    Quality goes hand in hand with price. If you buy a cheap Chinese-made DC pump like Waveline or Jebao you take your chances. If you buy a German-made pump like the Abyzz you pay a small fortune but you get a pump that runs very well, is absolutely silent, has enormous control capabilities, seems to last forever with little or no accumulation of calcium, and the much lower use of electricity becomes more noticeable the larger your aquarium and the size of your pumps is. Nineball’s 1350 gallon “Four Masters” tank is completely run on Abyzz pumps. Mr Saltwater Tank is quite correct, however, about the controllers: they do run extremely hot and have to be mounted with this in mind.

  • Damion says:

    Dave I agree that you’re playing with fire on a cheap return pump (someone get me fire extinguisher), but with wave pumps, I can buy 6 wp40’s for the price of 1 Tunze or Vortech of the same category, I’ve had 1 wp40 in my tank for 1 year no issues, I’ve just cleaned it and put it’s brand new twin in there for the next leap frog year. (Best $65 spent) There definitely are pros and cons to both. (I use Snap-on tools when it has the “must work” category, but Harbour Freight tools for the “other” stuff)

  • Karim says:

    You shouldn’t have to spend a small fortune (10x) for a decent quality pump. I’ve used multiple brands and they have failed, but it wasn’t the cheapest brand that failed. It was the midrange.

    When the cost of redundancy (2 lower cost pumps for backup) is lower than the cost of the premium version by more than 5x, the math doesn’t work for the premium.

  • Patrick says:

    I’ve run an ac return pump in the sump of my in my 46 gallon for almost a year. You have to either unplug on switch it off how you have it set up to do mantenece on your sump, such as vacuuming it out water changes etc, and cleaning it which can be a chore. I’m trying out a DC model for my new build (90 gallon) I like the features like 10 pause, slow start, different speeds, power off incase you run out of water (worse case scenario). Long brevity or not only time will tell. My DC circulation pumps made buy the same manufacture are 2 years old. But to note I’ve spent considerable more money on equipment with the big names and it died with in its first year. So any one of these technologies can and sometimes does fail. It’s all part of the experience…… Best advice I’ll give Is what I do, and have BACKUPS! If your prepared for an emergency, your prepare for life, it’s not if? But when, they’d why it’s called insurance. Have some of your own in BACKUPS. Anyway everything in this hobbiest is expensive, that doesn’t make it fool proof.

  • Frank says:

    My sump pump on my 180 is an AC supreme classic Model 18 and it has more than enough flow that I control thru a gate valve back into the sump return chamber. An added bonus is I can mix any additives in this chamber due to the turbulent flow. I have a backup as it is probably your most important life support piece of equipment. (Ditto what Patrick said!) Mark said it all in the last paragraph. Until DC pumps are proven I’ll stick with higher electric bills, dependability and peace of mind.

  • simon stirling says:

    Mark,

    I understand your point and generally agree however; did you not recommend the Tunze 1073.05 return pump? That is a DC pump with variable speed control…

    have you changed your mind on this particular pump??

  • ray briggs says:

    what are the pumps that are threaded on both ends. can,t find it. please help. thanks ray

  • Ray…you’re likely thinking of Danner Mag-drive pumps

  • RC says:

    Mr. saltwater tank guy, what about the very new Ecotech Vectra pumps???? I know reliability may not yet be known, but with a company like Ecotech I doubt they’re garbage. I would love to have you do a review on one…maybe soon??

Comments are closed.