This 400-gallon tank belongs to @maroun.c, a Reef2Reef staff member. It has a tank turnover of 21,000 gallons per hour.
This photo is from the Reef2Reef archives, courtesy of @maroun.c, ©2019, All Rights Reserved.
So, last time, in Part 1, we talked about water flow, why you need it in a reef tank, and tank turnover. Now let's talk about powerheads, which move the water around in your tank. I'm not going to talk about pumps bringing water back into your display tank from a sump because that's a very large topic in and of itself.
For the sake of discussion, let's say that you need more water movement than you are getting from a return pump and outlet. That's when you use powerheads.
Powerheads are simply small pumps that you place inside your display tank, fixed to an inside wall. They run on electricity, and they come in all shapes, sizes, price points, and functionalities.
How do you choose powerheads?
There is a dazzling array of choice for powerheads. Here are the major considerations:
1. How much water do you need to move?
You'll have to have already calculated how much flow you want. Since this is not an exact science, you can either get something more powerful than you need and dial it up or down, or aim for a certain amount of flow and add more powerheads later if you need them.
You can spend an unlimited amount of money on powerheads. You can spend all your money on powerheads. So, budget will be and should be a consideration for many readers. I noticed that both Hydor and Cobalt Aquatics have some very budget-friendly options.
There's an interesting thread happening in the forum on how newbies tend to get overwrought and preoccupied with having lots of bells and whistles that aren't needed for a successful reef tank. I highly recommend reading this thread. My point is that there are some really neat things happening in the evolution of powerheads, but that doesn't mean that you *need* these things for your tank.
3. What is the intended use of your powerhead?
This may sound stupid, but I'm not kidding. You don't need a top-of-the-line powerhead if its intended use is strictly to mix saltwater in a Rubbermaid bin. I, personally, bought the cheapest Cobalt Aquatics powerheads I could find for mixing saltwater, curing live rock, and for quarantine tanks.
4. AC versus DC
@Brew12 wrote an article about AC and DC pumps a couple of years ago. He has forgotten more about electricity than I will ever know, so I recommend reading his piece if you want to learn about the subtle differences. Basically, cheaper powerheads will be AC and more expensive controllable ones will be DC.
DC powerheads use less power and you could argue that they will last longer than an AC powerhead that you're turning on and off with a timer. But there are big differences in price between set-it-and-forget-it AC and controllable DC powerheads.
5. Space considerations
Some powerheads are bigger and some are smaller. EcoTech brand VorTech powerheads are the only ones at this time that have the business part (pump motor) of the powerhead *outside* the aquarium and the propeller only on the inside. For some people that's a big deal. In theory, having the motor on the outside also cuts down on heat transfer into the water. It's also arguably safer to have one less electrical cord immersed in the water.
Maxspect makes a big powerhead that's 12 inches long, but two of them with their controller are not exactly what I call cheap.
Screenshot from the Marine Depot website, courtesy of @Seawitch.
Well, most of brands talk about how quiet they are. You'll have to decide this for yourself. I don't know if there is any published data on powerhead noise comparisons. This is a question you could ask on the forum. I suspect that as you go up in price, you go down in noise level.
7. Controllers and controllability
If you have a sophisticated controller like Apex--or you aspire to have one some day--then you might want to choose powerheads that are compatible with it. Some brands have brand-specific controllers that will operate several powerheads, but just powerheads.
Be aware that if you choose two powerheads that will plug into one controller and use one power source, then the two powerheads typically operate as a "master" and "slave". You can't necessarily program each one to do something different.
And maybe you just want some controllability and having your powerheads change their flow patterns. None of the controllable powerheads I saw will change direction as part of their programming options, but they all offer change in flow patterns. And you can change the direction of flow manually if you want.
8. Coolness factor
I don't know if this is important to you, but Aqua Illumination has a powerhead that looks really cool--to me anyway. It has a dedicated controller or you can run it through their brand-specific app called MyAI.
Screenshot from the Premium Aquatics website, courtesy of @Seawitch.
I asked both Robert Farnsworth of Marine Depot and Luke Plank from Premium Aquatics if some powerheads were easier to clean than others, and they both said "not really". Then I asked if some were better or worse for getting livestock caught in them, and they both said again, not really. By the way, Robert did a good video on choosing powerheads that you might like to watch.
If you're very preoccupied with keeping livestock safe from powerheads, there are some DIY solutions that can be employed, and I'm aware of at least one 3D-printed powerhead guard available that Antonio Gutierrez of Vivid Creative Aquatics mentioned in his recent article. The Maxspect Gyre comes with some kind of special netting to wrap the powerhead and protect your livestock, and I think one other brand does too, but I'm not sure that particular netting really solves the problem.
When I started thinking about flow in my own aquarium, the first thing I thought of was some kind of nozzle that swivels. I don't know why none of these available powerheads have something like that (correct me if I'm wrong). I am aware of one that Vivid Creative Aquatics makes called The Random Flow Generator™ Nozzle, but that's for a pipe return, not a powerhead.
Photo is courtesy of Vivid Creative Aquatics, ©2019, All Rights Reserved.
So, it seems that in many respects you get what you pay for with powerheads. If you want them to have a lot of features, that costs big money. But you don't have to have all these features. You can buy equipment used, and you can also buy cheap powerheads and put them on a timer from a big-box store. In general, cheaper powerheads have a narrower stream of water coming out of them, and they're not terribly adjustable.
This concludes Part 2. In Part 3, I'll talk about powerhead placement.
Marine Depot, Premium Aquatics, Aqua Illumination, EcoTech Marine and Vivid Creative Aquatics are all sponsors of Reef2Reef. And I mention them in this article because I thought they were relevant, not because I had to.
We encourage all our readers to join the Reef2Reef forum. It’s easy to register, free, and reefkeeping is much easier and more fun in a community of fellow aquarists. We pride ourselves on a warm and family-friendly forum where everyone is welcome. You will also find lots of contests and giveaways with our sponsors.
Special thanks is due today to both Robert Farnsworth from Marine Depot and Luke Plank from Premium Aquatics, who both took time out of their busy days to answer questions from me. A lot of questions. I also want to thank Antonio Gutierrez of Vivid Creative Aquatics, who is very responsive and lets me use his photos freely in articles.
Author Profile: Cynthia White
Cynthia received her BA in English from NYU a long long time ago. She has been a freelance writer and editor for over 20 years. In 2018, she won the President's Award from the Professional Writers Association of Canada. Now she is a writer and editor on staff at R2R, where her forum nickname is Seawitch.
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