A Great Place for DC-Powered Pumps
Yesterday I wrote about why the DC powered protein skimmer excitement is nothing more than a fad that you can ignore.
And while I don’t think a DC powered pump on a skimmer is worth much of your attention, there are real benefits to using a DC powered pump for your return pump.
The choosing of a return pump is one of the biggest decisions in setting up a saltwater tank. Choose a pump with too little flow given your head pressure and the return pump won’t push any water up into your tank. Choose a pump with too much flow and your tank will sound like Niagra Falls from all the crashing water, regardless of your choice of overflows.
Often times you are left choosing a return pump that pushes more flow than you need and dialing it back through plumbing that returns part of the water back into the sump, therefore by passing the tank. This approach can get bulky, especially if you have a smaller sump.
If you get a pump that doesn’t push enough flow for your head pressure, you’ll have to purchase a bigger pump and hope you can return the smaller pump. Hint: stopping your tank build to return and swap out a return pump is highly annoying!
Enter the variable speed DC powered return pump. Flow rate too much? Turn it down. Need more flow, crank the pump up! 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.
You can also use the variable speed features to dial in the amount of water noise you are willing to tolerate. Any type of overflow system (durso, herbie, bean animal, etc) will have some amount of falling water noise. I’d rather make the adjustments at the pump vs. restricting water flow through valves or making the overflow system more complicated than it needs to be.
Finally, the impeller-saving soft start feature of these DC powered pumps is also nice as when your return pump impeller snaps, you’ve got a real problem on your hands unless you have a replacement on hand. Given that I’ve never had a return pump impeller break during my long saltwater tank career, I still like the soft start feature and a little bit of insurance never hurt.
Unlike a DC powered pump on a skimmer, the use of a DC powered return pump has real benefits that you can see and in this case, hear.
Browse the Store! Questions?
I agree with a lot of what you have said Mark. Wouldn’t you lose a lot of the functionality with the ramping up and down of the pumps when they are being controlled with a reef keeper, APEX, etc.?
That makes alot of sense Mark!!
Good idea! though with some simple enough math most can figure out the turnover rate and a good number. as for water noise, use a gurgle buster. dead silent, no water noise at the tank when its tuned properly. and i mean, none.
Nate
Still waiting to see some type of graph which shows flow rate vs head height for some o these DC pumps
Lee…I too was surprised that the flow rate v. head height graphs were out yet. They seem like an item you’d expect to see.
Bring in the graphs you manufacturers! Come on! What are ya??? Chicken??? Its not the size of the bell curve its the…ok yeah it is.
http://www.jlaquatics.com/images/flowcharts/speedwave_dc.jpg
Heres a graph I came across a while back when researching these guys.
Mark,
This might be a dumb question, but where do you get the dc pump with out the skimmer?
The DC pumps are made by a company called waveline for both the reef octopus and rlss. I have been using a dc waveline pump at the since October 2012 and I agree it is a great place to use it. The feed button that is on the controller makes for ease of use and restarts after ten minutes.
I have a DC powered skimmer as well.. I am waiting on the issues to be resolved with the DC powered pumps (non skimmer models) to be fixed prior to purchasing one for that use case. So far I have read many reports and was discouraged from purchasing a DC powered pump as a return or closed loop pump due to flow rate issues (something related to the pump controller). Not sure if these issues have been resolved as of yet. I recently purchased 2 x Waterblaster 10Ks instead of a Waveline 10500.
I do not think about getting a DC pump at first. I know from before Mark had one he showed on the older tanks setup he had. I seen the Reef Octopus pumps and Waveline pumps. Then I seen as how you can pick how much flow you need and that sold me. I got an Octopus DC pump and was happy to how much more flow came out as to the same flow rated pump I had on before. I has as said soft startup as it sounds as turbine engine starting. Plus the saving of the electric that is uses less.
Here a tip: I would hook what every pump you have it up to if you have a controller with a flow switch. If the water level goes down and you are away it will stop the pump and alarm will show. This will save it from burning up. I have it with the controller on a standby as when I feed the return pump turns off and the powerheads also and not push the food down the overflow.
side bar: pump regulation as a fad is of course- a fad. a FF or PS works by creating fine bubbles that have something of a dwell time. During that time, molecules of organic compounds ( starches, sugars amino acids and fractured proteins, dyes etc) attach to the rising bubble and are lifted out of solution by the fomate formed. pretty straight forward stuff. No need to regulate as our guru here has stated so well.
But what does amaze me in this hobby is how backward understanding of basic pipe plumbing is?? As a 101 fundamental eye opener—
water should NOT be forced thru a pvc pipe– it should ‘flow’ thru the pipe. There is a nagging image in the mind of newbies that force will a) push MORE water thru and B) that once forced thru, water under great pressure will move massive amounts of water within the closed system. NOT TRUE. PVC pipe and bends in fittings will reduce flow due to wall friction. The idea is to use larger pipe to allow flow to maximize. It is the VOLUME of water and not the force/speed of water that creates maximum flow strength. To illustrate this, those beginners that think of outlets as swimming pool eyelets that push and sweep water into the tank will be destine to fail in their visionary designs ideas. ONE manifold with slightly larger diameter piping ( on big systems I have gone to 2 inches and in some cases, even 3 inches with sweeps and not right angle fittings- especially on the gravity side) will deliver the most water and the greatest current inside the tank. Done right and power heads are made obsolete. See posts on circulation loops– JasPR
Brandon. Try the Waveline DC pumps. http://www.rlss.ca/
I tried one of the more recently released DC pumps… for my head height of 12′ it’s supposed to give me 3000+ gph.. lucky if i”m getting 600gph.. mfg suggested I also get a small fan to keep controller and power inverter cooled. NOT impressed.. if anyone knows of a DC pump which will get me 1200 gph at 12′ of head, I’d be glad to hear.