Sump pumps - a (fish) wifes tale?

[RhumbRunner]

Does anyone have experience running a sump pump on a wavemaker or timer? From what I've been able to find on this site the opinion is invariably a pump failure. Is this just another (fish) 'wifes tale', or is it true? If so why? What was the on/off cycle and how long did the pump take to fail? If powerheads work with these wavemakers, why do sump pumps fail?

Tried this in another forum but got no response from those who have actually experienced this. Thought I would try it here for those who can explain the phenomenon even if they haven't experienced it. Is this something in the inherent nature of sump pumps? Have at least 2 (3 if I count the fridge) that operate 24/7 for years without failure. The FHW pump comes on and off during the winter up here every 15 minutes or so. The well pump (in the basement - not submersed in the well) coupled to a 30gal holding tank, can go on and off 100 times a day during the summer when I'm watering the garden. Is there something in the inherent design of a Mag, Iwaki etc. that would make them fail?

Thanks for any information.

[maximus89]

I would look into these before you make any hasty desicions they just alternate the current from your pump pump stays running 24/7 http://www.marinedepot.com/a_wm_scwd.asp?CartId=

[RhumbRunner]

Thanks for the reply, maximus89. The SCWD or Sea Swirls don't really apply here for a number of reasons most importantly (at least to me) is just why the common wisdom says that sump pumps fail on timers when powerheads do not. I've not been able to get a single response from anyone who has actually done this and experienced a failure traceable to the intermittent action of the pump. Beginning to think this is a case where empirical evidence rules. I.E. buy the Mag 9, a Natural Wave Timer and run them on minimal cycle (20 secs) for a few months in a benchmark tank to see what happens.

FWIW: this is the response I received from Drs Foster & Smith when I posted a similar question to them. Not sure it really defines the pump failure issue (which seems to be motor related) but they deserve kudos for timely and logical responses which are on target.



Dear Steve,

Thank you for your inquiry. In general, most pumps will fail when run on a wave maker or timer. This is because the impellers are designed with a very small plastic piece that actually grabs the impeller blades, and this plastic piece can break very easily.
The Iwaki pumps are designed much differently as their impeller is completely inclosed and one solid piece. These pumps can handle the constant on/off cycle of a timer with no problems. If we can be of additional assistance, please contact our Live Aquaria department at 1-800-334-3699, or via email and we will be happy to answer any question(s) you may have.

Sincerely,
Greg
Live Aquaria
Customer Service

[H20ENG]

Hey Rhumb,
One factor could be that the motor windings just get stressed from all the starts (stops wont do any harm). There is a great inrush of current to get a motor spinning, and over time, hot spots may develop internally. Eventually, the windings will "burn out", meaning that one of the looong wires used to build the stator will separate, opening the circuit. This will cause the alternate windings to overamp, and fry the rest of the motor.
Some pumps with heavier motors will take it, some of the cheapie pumps wont.
$0.02
Chris

[RhumbRunner]

H20,
Thanks for the 2. Just might be, especially in the case of a fried motor. From personal experience, I'd go for the bearings or armature wearing out of true. Almost certainly it’s a result of the force exerted to start the motor and think it’s a result of the linear force trying to pull the armature out of true rather than the radial force (torque) applied during rotation, but I’m really dancing in the dark here. When this happens the permanent magnets grab hold of the electros and if left that way, the result if that wonderful smell of southern fried rotor. Just a guess but ever notice how you can get a an old window fan to work when you thought it was dead just by spinning the blades during startup? Anyway, don't know why this is more common in a sump pump on a timer (which based solely on the price, would seem to be of sterner stuff) than in a power head which seems to be able to accommodate this with impunity.
Big disappointment is, after doing a search on this and reading dozens of admonitions against same, I haven't seen a single response that actually documented the experience or suggested a plausible explanation for same (present company excluded, of course:-).
Time for a trip to Empirical Park to watch the outcome.

Later, Steve

[H20ENG]

Steve,
I agree that for the $ they charge for this stuff, it ought to take whatever we throw at it.
I wonder if there is a different rating for start / stops, as opposed to "continuous duty" since starts are harder on the motors than just running. A sump pump may start a BUNCH of times a day in a wet pit. If you could find a corrosion resistant unit, you could start it all you want. These industrial units will be $$$, though.
Off the subject, but speaking of axial thrust, Our 365 ton centrifugal chillers have built in safeties in which the inlet vanes have switches to shut down the chiller if the amperage does not correspond to the vane angle. In short, its to prevent the impeller (18,000rpm) from sucking itself down the suction line and cooking the axial bearing.
A couple of years ago, the electric company gave us a current imbalanced feed. This caused the motor to "wobble" and it ate it up in about 10 minutes. They paid the $30K repair bill.:eek1:

[northernreefer]

I think that water movement in a reef aquarium is an issue that has been totally discounted in the design of most reef aquariums. As Eric Borneman has pointed out in his recent work, the three most important conditions for sps corals in order of importance is food (phyto and ZOOplankton!), WATER MOVEMENT, and last is lighting!

I have been in the hobby for over 25 years and have used EVERY type of filtration. I HATE sumps. They are a source of many different problems, they are hard to work on, they are noisy, they are a great source of probable FLOODS!

The last 7 years, I have been designing my systems with top mounted filtration. My filters consist simply of the largest rubbermaid containers that I can find and fit into the equipment room behind the aquarium. ALL that is in the aquarium is a pvc drilled inlet pipe!!!! The inlet pipe feeds the pump, which in turn pumps the water into the top mounted filter/refugium/algae scrubber/ WAVE MAKER!

Eric Borneman in his corals book has the design for a flush valve that he calls the Borneman flush device. Actually, Martin Moe developed this system. It is basically a toilet valve with a float attached to the flapper. You can adjust the frequency and volume of water that gets flushed by altering the length on the line attached to the flapper. Unbelievable water movement! The corals and fish absolutely love it! In fact many of the fish learn that amphipods and copepods get flushed into the aquarium, and will wait for the flush and search for this food!

My latest project was a 120 with dual top mounted filters! They are 29 gallon rubbermaids reinforced with pvc. The two filters are adjustable, and flush independently! The water movement is damn near the real thing! Both of the filters cantain large amounts of live rock and caulerpa illuminated opposite of the aquarium lighting. ZERO nitrates with no water changes and a super stable high pH of 8.4!

The system that I am currently working on is a 75 gallon. I do not have a room or closet behind the aquarium, so I am building a tall canopy that will house the filter. This is really an awesome filtration system for any reef aquarium!

I attend all of the MACNA and was at the first IMAC conference, and one thing in common with all of the experts in the field is; DROP THE FANCY EQUIPMENT AND DO IT THE WAY NATURE DOES IT!!

[RhumbRunner]

northernreefer:

Agree with your (and Borneman's) opinion on water movement and this thread was motivated, if not specifically related, to same. But your reply, while interesting and even elegant in one respect, doesn't seem to apply to the original question (see the opening thread).

Some thoughts by way of a reply:
. Filtration and water movement are not synonymous but related. Powerheads provide all the necessary water movement in a tank but provide NO filtration. What ever filtration occurs is not a result of the powerhead but the water movement generated thru the tank and the tanks ability to biologically process same.
. The same applies to sumps, where ever they are located. They neither provide any filtration or water movement but serve as a convent place to house the mechanical apparatus necessary to accomplish both. You say you hate sumps! Yet, your description of your system two sumps (with refugiums?).
. Your objection seems to be with sumps (fuges?) located beneath the display tank. Understandable, but not definitive. That they are hard to work with is probably true, but are they any harder to work with if they are located above the tank (I have 8' ceilings)? Not sure what you mean by many different problems, care to amplify on this? Flooding is a problem with any sump/fuge setup. The answer is to size the tank and sump/fuge such that no amount of water draining (pumping in your case) can exceed the ability of the sump/fuge capacity and no amount of water being pumped (or drained) from the sump/fuge can exceed the tanks capacity. That you had a separate room to house your sumps is wonderful. Most of us don't. It really changes nothing but your ability to work on both more conveniently. The water must be moved from one place to another and that requires a pump. The chances of flooding are the same, although the effects may be less dramatic in your sump/fuge room:-).

Would like to hear more about the flapper/surge returns from your sump(s). Think that is the really elegant point is your reply. Start a thread. Make us smart.


Later, Steve